Engwerda, E.E.; Tack, C.J.J.; Galan, B.E. de
OBJECTIVE: Clamp studies have shown that the absorption and action of rapid-acting insulin are faster with injection by a jet injector than with administration by conventional pen. To determine whether these pharmacokinetic changes also exist in patients with diabetes and benefit postprandial
Pollock, R F; Valentine, W J; Pilgaard, T; Nishimura, H
The Nippon Ultra-Rapid Insulin and Diabetic Complication Evaluation Study (NICE Study) (NCT00575172) was a 5-year, open-label, randomised controlled trial which compared cardiovascular outcomes in Japanese type 2 diabetes patients intensively treated with regular human insulin or insulin aspart (NovoRapid; Novo Nordisk A/S, Bagsvaerd, Denmark), a rapid-acting insulin analogue. The aim of the present analysis was to evaluate the cost effectiveness of insulin aspart versus regular human insulin from the perspective of a Japanese third-party healthcare payer. A discrete event-simulation model was developed in Microsoft Excel to assess the within-trial cost effectiveness and make longer-term clinical projections in patients treated with regular human insulin or insulin aspart. In addition to severe hypoglycaemia, the model captured myocardial and cerebral infarction events and percutaneous coronary intervention and coronary artery bypass graft procedures. Within-trial mortality, incidence of severe hypoglycaemia and cardiovascular event probabilities were derived from the annual rates observed during the trial period, while post-trial outcomes were calculated using the event rates from the trial, adjusted for increasing patient age. Event costs were accounted from the healthcare payer perspective and expressed in 2008 Japanese yen (JPY), while health-related quality of life (HRQoL) was captured using event and state utilities. Future costs and clinical benefits were discounted at 3% annually. Life expectancy, quality-adjusted life expectancy, cardiovascular event rates and costs were evaluated over 5- and 10-year time horizons and sensitivity analyses were performed to assess variability in model outcomes. Over 5 years of treatment, insulin aspart dominated human insulin both in incremental life expectancy and in incremental quality-adjusted life-years (QALYS). Insulin aspart was associated with a small improvement in discounted life expectancy of 0.005 years (4.688 vs
Safety and efficacy of a glucagon-like peptide-1 receptor agonist added to basal insulin therapy versus basal insulin with or without a rapid-acting insulin in patients with type 2 diabetes: results of a meta-analysis.
Wysham, Carol H; Lin, Jay; Kuritzky, Louis
To consolidate the evidence from randomized controlled trials evaluating the use of glucagon-like peptide-1 receptor agonists (GLP-1 RAs) as add-on to basal insulin therapy in type 2 diabetes (T2D) patients. We searched the EMBASE® and NCBI PubMed (Medline) databases and relevant congress abstracts for randomized controlled trials evaluating the efficacy and safety of GLP-1 RAs as add-on to basal insulin compared with basal insulin with or without rapid-acting insulin (RAI) through 23 May 2016. The pooled data were analyzed using a random-effects meta-analysis model. A subanalysis was performed for trials investigating basal insulin plus GLP-1 RAs versus basal insulin plus RAI. Of the 2617 retrieved records, 19 randomized controlled trials enrolling 7,053 patients with T2D were included. Compared with basal insulin ± RAI, reduction in glycated hemoglobin (HbA1c) from baseline (difference in means: -0.48% [95% confidence interval (CI), -0.67 to -0.30]; p insulin plus GLP-1 RA. The subanalysis similarly showed significant results for change in HbA1c from baseline and for weight loss, as well as a significantly lower risk of symptomatic hypoglycemia in patients treated with basal insulin plus GLP-1 RA versus basal insulin plus RAI (odds ratio, 0.52 [95% CI, 0.42 to 0.64]; p insulin provided improved glycemic control, led to weight reduction and similar hypoglycemia rates versus an intensified insulin strategy; however, symptomatic hypoglycemia rates were significantly lower when compared with a basal insulin plus RAI.
Simulation-Based Evaluation of Dose-Titration Algorithms for Rapid-Acting Insulin in Subjects with Type 2 Diabetes Mellitus Inadequately Controlled on Basal Insulin and Oral Antihyperglycemic Medications.
Ma, Xiaosu; Chien, Jenny Y; Johnson, Jennal; Malone, James; Sinha, Vikram
The purpose of this prospective, model-based simulation approach was to evaluate the impact of various rapid-acting mealtime insulin dose-titration algorithms on glycemic control (hemoglobin A1c [HbA1c]). Seven stepwise, glucose-driven insulin dose-titration algorithms were evaluated with a model-based simulation approach by using insulin lispro. Pre-meal blood glucose readings were used to adjust insulin lispro doses. Two control dosing algorithms were included for comparison: no insulin lispro (basal insulin+metformin only) or insulin lispro with fixed doses without titration. Of the seven dosing algorithms assessed, daily adjustment of insulin lispro dose, when glucose targets were met at pre-breakfast, pre-lunch, and pre-dinner, sequentially, demonstrated greater HbA1c reduction at 24 weeks, compared with the other dosing algorithms. Hypoglycemic rates were comparable among the dosing algorithms except for higher rates with the insulin lispro fixed-dose scenario (no titration), as expected. The inferior HbA1c response for the "basal plus metformin only" arm supports the additional glycemic benefit with prandial insulin lispro. Our model-based simulations support a simplified dosing algorithm that does not include carbohydrate counting, but that includes glucose targets for daily dose adjustment to maintain glycemic control with a low risk of hypoglycemia.
Matthew D Campbell
Full Text Available To examine the metabolic, gluco-regulatory-hormonal and inflammatory cytokine responses to large reductions in rapid-acting insulin dose administered prandially before and after intensive running exercise in male type 1 diabetes patients.This was a single centre, randomised, controlled open label study. Following preliminary testing, 8 male patients (24±2 years, HbA1c 7.7±0.4%/61±4 mmol.l-1 treated with insulin's glargine and aspart, or lispro attended the laboratory on two mornings at ∼08:00 h and consumed a standardised breakfast carbohydrate bolus (1 g carbohydrate.kg-1BM; 380±10 kcal and self-administered a 75% reduced rapid-acting insulin dose 60 minutes before 45 minutes of intensive treadmill running at 73.1±0.9% VO2peak. At 60 minutes post-exercise, patients ingested a meal (1 g carbohydrate.kg-1BM; 660±21 kcal and administered either a Full or 50% reduced rapid-acting insulin dose. Blood glucose and lactate, serum insulin, cortisol, non-esterified-fatty-acids, β-Hydroxybutyrate, and plasma glucagon, adrenaline, noradrenaline, IL-6, and TNF-α concentrations were measured for 180 minutes post-meal.All participants were analysed. All glycaemic, metabolic, hormonal, and cytokine responses were similar between conditions up to 60 minutes following exercise. Following the post-exercise meal, serum insulin concentrations were lower under 50% (p<0.05 resulting in 75% of patients experiencing hyperglycaemia (blood glucose ≥8.0 mmol.l-1; 50% n = 6, Full n = 3. β-Hydroxybutyrate concentrations decreased similarly, such that at 180 minutes post-meal concentrations were lower than rest under Full and 50%. IL-6 and TNF-α concentrations remained similar to fasting levels under 50% but declined under Full. Under 50% IL-6 concentrations were inversely related with serum insulin concentrations (r = -0.484, p = 0.017.Heavily reducing rapid-acting insulin dose with a carbohydrate bolus before, and a meal after intensive
Campbell, Matthew D.; Walker, Mark; Trenell, Michael I.; Jakovljevic, Djordje G.; Stevenson, Emma J.; Bracken, Richard M.; Bain, Stephen C.; West, Daniel J.
OBJECTIVE To examine the acute and 24-h glycemic responses to reductions in postexercise rapid-acting insulin dose in type 1 diabetic patients. RESEARCH DESIGN AND METHODS After preliminary testing, 11 male patients (24 ± 2 years, HbA1c 7.7 ± 0.3%; 61 ± 3.4 mmol/mol) attended the laboratory on three mornings. Patients consumed a standardized breakfast (1 g carbohydrate ⋅ kg−1 BM; 380 ± 10 kcal) and self-administered a 25% rapid-acting insulin dose 60 min prior to performing 45 min of treadmill running at 72.5 ± 0.9% VO2peak. At 60 min postexercise, patients ingested a meal (1 g carbohydrate ⋅ kg−1 BM; 660 ± 21 kcal) and administered a Full, 75%, or 50% rapid-acting insulin dose. Blood glucose concentrations were measured for 3 h postmeal. Interstitial glucose was recorded for 20 h after leaving the laboratory using a continuous glucose monitoring system. RESULTS All glycemic responses were similar across conditions up to 60 min postexercise. After the postexercise meal, blood glucose was preserved under 50%, but declined under Full and 75%. Thence at 3 h, blood glucose was highest under 50% (50% [10.4 ± 1.2] vs. Full [6.2 ± 0.7] and 75% [7.6 ± 1.2 mmol ⋅ L−1], P = 0.029); throughout this period, all patients were protected against hypoglycemia under 50% (blood glucose ≤3.9; Full, n = 5; 75%, n = 2; 50%, n = 0). Fifty percent continued to protect patients against hypoglycemia for a further 4 h under free-living conditions. However, late-evening and nocturnal glycemia were similar; as a consequence, late-onset hypoglycemia was experienced under all conditions. CONCLUSIONS A 25% pre-exercise and 50% postexercise rapid-acting insulin dose preserves glycemia and protects patients against early-onset hypoglycemia (≤8 h). However, this strategy does not protect against late-onset postexercise hypoglycemia. PMID:23514728
An additional bolus of rapid-acting insulin to normalise postprandial cardiovascular risk factors following a high-carbohydrate high-fat meal in patients with type 1 diabetes: A randomised controlled trial.
Campbell, MD; Walker, M. (Mark); Ajjan, RA; Birch, KM; Gonzalez, JT; West, DJ
AIM: To evaluate an additional rapid-acting insulin bolus on postprandial lipaemia, inflammation and pro-coagulation following high-carbohydrate high-fat feeding in people with type 1 diabetes. METHODS: A total of 10 males with type 1 diabetes [HbA1c 52.5 ± 5.9 mmol/mol (7.0% ± 0.5%)] underwent three conditions: (1) a low-fat (LF) meal with normal bolus insulin, (2), a high-fat (HF) meal with normal bolus insulin and (3) a high-fat meal with normal bolus insulin with an additional 30% insulin...
Mikiewicz, Diana; Bierczyńska-Krzysik, Anna; Sobolewska, Agnieszka; Stadnik, Dorota; Bogiel, Monika; Pawłowska, Monika; Wójtowicz-Krawiec, Anna; Baran, Piotr A.; Łukasiewicz, Natalia; Romanik-Chruścielewska, Agnieszka; Sokołowska, Iwona; Stadnik, Jacek; Borowicz, Piotr; Płucienniczak, Grażyna; Płucienniczak, Andrzej
The discovery of insulin led to a revolution in diabetes management. Since then, many improvements have been introduced to insulin preparations. The availability of molecular genetic techniques has enabled the creation of insulin analogs by changing the structure of the native protein in order to improve the therapeutic properties. A new expression vector pIBAINS for production of four recombinant human insulin (INS) analogs (GKR, GEKR, AKR, SR) was constructed and overexpressed in the new E. coli 20 strain as a fusion protein with modified human superoxide dismutase (SOD). The SOD gene was used as a signal peptide to enhance the expression of insulin. SOD::INS was manufactured in the form of insoluble inclusion bodies. After cleavage of the fusion protein with trypsin, the released insulin analogs were refolded and purified by reverse-phase high performance liquid chromatography (RP-HPLC). Elongation of chain A, described here for the first time, considerably improved the stability of the selected analogs. Their identity was confirmed with mass spectrometric techniques. The biological activity of the insulin derivatives was tested on rats with experimental diabetes. The obtained results proved that the new analogs described in this paper have the potential to generate prolonged hypoglycemic activity and may allow for even less frequent subcutaneous administration than once-a-day. When applied, all the analogs demonstrate a rapid onset of action. Such a combination renders the proposed biosynthetic insulin unique among already known related formulations. PMID:28296883
Mikiewicz, Diana; Bierczyńska-Krzysik, Anna; Sobolewska, Agnieszka; Stadnik, Dorota; Bogiel, Monika; Pawłowska, Monika; Wójtowicz-Krawiec, Anna; Baran, Piotr A; Łukasiewicz, Natalia; Romanik-Chruścielewska, Agnieszka; Sokołowska, Iwona; Stadnik, Jacek; Borowicz, Piotr; Płucienniczak, Grażyna; Płucienniczak, Andrzej
The discovery of insulin led to a revolution in diabetes management. Since then, many improvements have been introduced to insulin preparations. The availability of molecular genetic techniques has enabled the creation of insulin analogs by changing the structure of the native protein in order to improve the therapeutic properties. A new expression vector pIBAINS for production of four recombinant human insulin (INS) analogs (GKR, GEKR, AKR, SR) was constructed and overexpressed in the new E. coli 20 strain as a fusion protein with modified human superoxide dismutase (SOD). The SOD gene was used as a signal peptide to enhance the expression of insulin. SOD::INS was manufactured in the form of insoluble inclusion bodies. After cleavage of the fusion protein with trypsin, the released insulin analogs were refolded and purified by reverse-phase high performance liquid chromatography (RP-HPLC). Elongation of chain A, described here for the first time, considerably improved the stability of the selected analogs. Their identity was confirmed with mass spectrometric techniques. The biological activity of the insulin derivatives was tested on rats with experimental diabetes. The obtained results proved that the new analogs described in this paper have the potential to generate prolonged hypoglycemic activity and may allow for even less frequent subcutaneous administration than once-a-day. When applied, all the analogs demonstrate a rapid onset of action. Such a combination renders the proposed biosynthetic insulin unique among already known related formulations.
Mastrorilli, Carla; Rizzuti, Laura; Cangelosi, Antonina Marta; Iovane, Brunella; Chiari, Giovanni; Caffarelli, Carlo
Insulin allergy has been uncommon since the introduction of human recombinant insulin preparations; the prevalence is 2.4%. Insulin injection could elicit immediate reactions, which are usually induced by an IgE-mediated mechanism, within the first hour after drug administration. In the present study, we describe the case of a child who experienced immediate urticaria after long-acting insulin injection. A 9-year-old girl affected by type I diabetes mellitus referred a history of three episodes of urticaria 30 min after insulin subcutaneous injection. During the first week of insulin therapy, she developed generalized immediate urticaria twice after long-acting insulin glargine first and then once after insulin degludec administration. Symptoms resolved within a few hours after treatment with oral antihistamine. She tolerated rapid insulin lispro. Her personal allergological history was negative. Skin prick tests with degludec, glargine and detemir were performed, showing negative results. Intradermal 1:100000-diluted tests were immediately positive for both degludec and glargine but not for detemir. In light of these findings, detemir was administered without any reaction. Our results show that detemir is tolerated by patients with clinical hypersensitivity reactions to degludec and glargine. Although reactions could be attributable to additives allergy, such as zinc or metacresol, this was excluded since all three preparations contain the same components. So, insulin itself acted as offending allergen. Detemir differs from degludec and glargine in a few aminoacids. Therefore, it is possible that the conformational rather than the linear epitope may be responsible for the reaction. This result suggests integrating intradermal tests in the diagnostic flowchart for insulin allergy. Insulin allergy should always be suspected in patients with immediate symptoms after drug injection. As allergologic work-up, prick by prick test and intradermal test to insulin
... Text Size: A A A Listen En Español Insulin Basics There are different types of insulin depending ... you may be experiencing a reaction. Types of Insulin Rapid-acting insulin , begins to work about 15 ...
Darmon, P; Raccah, D
Type 2 diabetes is an evolutive disease with a progressive defect of beta-cell insulin secretion. This characteristic points to a need for treatment that takes into account such a natural history. When oral antidiabetic drugs fail to achieve the patient's target HbA1c level, basal insulin treatment is usually initiated and titrated in association with oral drugs to manage fasting hyperglycaemia. Over a period of time, it is enough to simply achieve the HbA1c target. However, when even a good fasting blood glucose level is no longer sufficient to control overall glycaemia, then prandial treatment must be combined with the titrated basal insulin to deal with the postprandial hyperglycaemia responsible for the elevation of HbA1c. Of the different therapeutic options now available for this, rapid-acting insulins and GLP-1 receptor agonists (RAs) can be used. Rapid-acting insulins can be added either at each meal, achieving full insulin supplementation with a basal-bolus regimen, or at the main meal only as a "basal-plus" regimen. Compared with the full basal-bolus, the basal-plus strategy is associated with fewer injections, yet provides similar efficacy in terms of HbA1c improvement, but with less weight gain and lower hypoglycaemic risk. As for GLP-1 RAs, numerous studies, and especially those using short-acting GLP-1 RAs, have demonstrated more pronounced effects on postprandial hyperglycaemia, good complementary effects with basal insulin, and significant improvement of HbA1c with no weight gain and a low risk of hypoglycaemia. Similarly, direct and indirect comparisons of the use of rapid-acting insulins and GLP-1 RAs to intensify basal insulin have shown comparable efficacy in terms of HbA1c control, but with less weight gain and fewer hypoglycaemic episodes with GLP-1 RAs. Copyright © 2015 Elsevier Masson SAS. All rights reserved.
Olczyk, Paweł; Komosinska-Vassev, Katarzyna; Ramos, Paweł; Mencner, Łukasz; Olczyk, Krystyna; Pilawa, Barbara
Electron paramagnetic resonance (EPR) spectroscopy was used to examine insulins interactions with free radicals. Human recombinant DNA insulins of three groups were studied: short-acting insulin (Insuman Rapid); intermediate-acting insulins (Humulin N, Insuman Basal), and pre-mixed insulins (Humulin M3, Gensulin M50, Gensulin M40, Gensulin M30). The aim of an X-band (9.3GHz) study was comparative analysis of antioxidative properties of the three groups of human insulins. DPPH was used as a stable free radical model. Amplitudes of EPR lines of DPPH as the paramagnetic free radical reference, and DPPH interacting with the individual tested insulins were compared. For all the examined insulins kinetics of their interactions with free radicals up to 60 min were obtained. The strongest interactions with free radicals were observed for the short-acting insulin - Insuman Rapid. The lowest interactions with free radicals were characteristic for intermediate-acting insulin - Insuman Basal. The pre-mixed insulins i.e. Humulin M3 and Gensulin M50 revealed the fastest interactions with free radicals. The short acting, intermediate acting and premixed insulins have been found to be effective agents in reducing free radical formation in vitro and should be further considered as potential useful tools in attenuation of oxidative stress in diabetic patients. Copyright © 2015 Elsevier B.V. All rights reserved.
Garrido Carrasco, Elizabeth; Servicio de Endocrinología, Hospital Nacional Edgardo Rebagliati Martins, Lima, Perú
Insulin analogues are a new pharmaceutical family, designed to overcome deficiencies that still exist with the rDNA insulin. There are rapid-acting insulin analogues such as lispro insulin and insulin aspart. They avoid postprandial and nocturnal hypoglycemia. There are also intermediate-acting insulin analogues like NPL and Mix 25 (a mixture between NPL and lispro), which join the neutral protamine insulin length of action and the fast onset of the rapid-acting analogue lispro. Finally, ther...
DeVries, J. Hans
Insulin pump therapy enjoys a steadily growing number of users and is associated with an approximately 0.5% lower A1c as compared to flexible insulin injection therapy in type 1 diabetes patients. An important question is whether superiority of insulin pump therapy persists in the era of rapid
Ivan Ivanovich Dedov
Full Text Available Achieving optimal glycemic control is an important aspect of preventing and slowing the progression of diabetes-associated complications, and reducing the cost of their treatment. Long-acting insulin analogues, glargine and detemir, provide better metabolic control with reduced risk of hypoglycaemia as compared to NPH insulin. However, fear of hypoglycaemia and weight gain, as well as the complexity of regimen, are still the most important barriers to well-timed initiation and intensification of insulin therapy. Insulin degludec (Tresiba® is a new ultra-long-acting insulin analogue. After subcutaneous injection degludec forms repository of soluble multi-hexamers, which are gradually absorbed to the bloodstream, providing a flat, stable antihyperglycemic effect lasting more than 42 h, and low intra-individual variability as opposed to currently used basal insulin analogues, insulin glargine and insulin detemir. In the seven randomized, open label, controlled phase 3 trials lasting 26 or 52 weeks, using treat-to-target (no more non-inferiority design, insulin degludec provided glycemic control similar to that of insulin glargine with lower risk of nocturnal hypoglycaemia and good safety profile in patients with type 1 or 2 diabetes. Furthermore, trials examining a flexible dosing regimen of insulin degludec in patients with type 1 or 2 diabetes have shown that it is possible to vary the injection time without compromising glycemic control or safety of the therapy.
Liminet, Christelle; Vouillarmet, Julien; Chikh, Karim; Disse, Emmanuel
We report the case of a patient with diabetes presenting a severe insulin-resistance syndrome due to the production of insulin autoantibodies by a lymphocytic lymphoma. We describe the various mechanisms leading to the production of insulin autoantibodies and insulin receptor autoantibodies and review the therapeutic possibilities. Copyright © 2016 Canadian Diabetes Association. Published by Elsevier Inc. All rights reserved.
Full Text Available Fei Wang,1 Justine Surh,1 Manmeet Kaur21University of Connecticut School of Pharmacy, Department of Pharmacy Practice, Storrs, 2Joslin Diabetes Center Affiliate, Hospital of Central Connecticut, New Britain, CT, USABackground: Insulin degludec (IDeg is a neutral, ultralong-acting new generation basal insulin analog developed by NovoNordisk currently in Phase III clinical development. IDeg offers a duration of action of more than 42 hours in adults, much longer than current basal insulin formulations.Objective: The aim of this review is to assess the efficacy and safety data of IDeg in the treatment of type 1 and type 2 diabetes mellitus.Methods: Relevant English language articles from 2010 to 2012 were identified through MEDLINE, PubMed, EMBASE, Scopus, BIOSIS, and Google Scholar. Online conference proceedings of the 71st ADA Scientific Sessions and the 47th EASD Annual Meeting were reviewed. Studies were compared in terms of their study designs, primary and secondary efficacy parameters, and tolerability data.Results: There are a total of nine published trials investigating the clinical efficacy and safety of IDeg in over 3000 subjects with type 1 and 2 diabetes. Only three trials were published in full. All were open-label, randomized multicenter trials with durations of 16 to 52 weeks. IDeg and coformulations of IDeg with insulin aspart (IAsp were compared to insulin glargine (IGlar, detemir, and biphasic IAsp 30 (BIAsp 30.Conclusion: Based upon the available evidence, there appear to be no reported differences between IDeg and IGlar, detemir, or BIAsp 30 in the reduction of the primary efficacy end-points of HbA1c and mean fasting plasma glucose (FPG concentrations. Only flexible dosing of IDeg provided a significant reduction in FPG compared to IGlar. IDeg demonstrated a significant reduction in nocturnal hypoglycemia in type 1 diabetes. In type 2 diabetes, IDeg reduced the incidence of hypoglycemia by 18% and 58% compared to IGlar and
Full Text Available Background. The purpose of the study was a retrospective comparative analysis of using insulin analogues of the prolonged and ultra-short action and human genetically engineered insulins of middle and short action in children and adolescents with type 1 diabetes mellitus (DM. Materials and methods. The influence of ultra-rapid insulin analog in comparison with human rapid-action insulin on the course of type 1 DM in 100 children and adolescents was studied. It was applied as basal-bolus regimen of insulin therapy. Analysis of parameters which reflect criteria of insulin therapy effectiveness, positive effect of ultra-rapid insulin analog on the course of DM has been performed. Results. Application of ultra-rapid insulin analog before each meal improved parameters of pre- and postprandial glycemia, decreased the range of fluctuations of blood sugar during the day, reduced and maintained HbA1c level without augmentation of frequency and intensity of hypoglycaemia, and also decreased the level of noctural hypoglycaemia. Conclusions. The ultra-rapid insulin analog is the drug of choice for the effective use in insulin pumps.
Winkelman, L A; Overton, T R
This study investigated the effect of 2 different types of long-acting insulin on milk production, milk composition, and metabolism in lactating dairy cows. Multiparous cows (n=30) averaging 88 d in milk were assigned to one of 3 treatments in a completely randomized design. Treatments consisted of control (C), Humulin-N (H; Eli Lilly and Company, Indianapolis, IN), and insulin glargine (L). The H and L treatments were administered twice daily at 12-h intervals via subcutaneous injection for 10d. Cows were milked twice daily, and milk composition was determined every other day. Mammary biopsies were conducted on d 11, and mammary proteins extracted from the biopsies were analyzed by Western blot for components of insulin and mammalian target of rapamycin signaling pathways. Treatment had no effect on dry matter intake or milk yield. Treatment with both forms of long-acting insulin increased milk protein content and tended to increase milk protein yield over the 10-d treatment period. Analysis of milk N fractions from samples collected on d 10 of treatment suggested that cows administered L tended to have higher yields of milk protein fractions than cows administered H. Milk fat content and yield tended to be increased for cows administered long-acting insulins. Lactose content and yields were decreased by treatment with long-acting insulins. Administration of long-acting insulins, particularly L, tended to shift milk fatty acid composition toward increased short- and medium-chain fatty acids and decreased long-chain fatty acids. Plasma concentrations of glucose and urea N were lower for cows administered long-acting insulins; interactions of treatment and sampling time were indicative of more pronounced effects of L than H on these metabolites. Concentrations of nonesterified fatty acids and insulin were increased in cows administered long-acting insulins. Decreased concentrations of urea N in both plasma and milk suggested more efficient use of N in cows
Ramos, Analía; Zapata, Lluis; Vera, Paula; Betbese, Antoni J; Pérez, Antonio
The optimal initial dose of subcutaneous (SC) insulin after intravenous (IV) infusion is controversial, especially in patients receiving continuous enteral nutrition (EN) or total parenteral nutrition (TPN). The aim of this study was to evaluate the strategy used at our hospital intensive care unit (ICU) in patients switched from IV insulin to SC insulin glargine while receiving EN or TPN. A retrospective analysis was made of 27 patients on EN and 14 on TPN switched from IV infusion insulin to SC insulin. The initial dose of SC insulin was estimated as 50% of the daily IV insulin requirements, extrapolated from the previous 12h. A corrective dose of short-acting insulin (lispro) was used when necessary. Mean blood glucose (BG) level during SC insulin treatment was 136±35mg/dL in the EN group and 157±37mg/dL in the TPN group (p=0.01). In the TPN group, mean BG was >180mg/dL during the first three days after switching, and a 41% increase in the glargine dose was required to achieve the target BG. In the EN group, mean BG remained <180mg/dL throughout the days of transition and the dose of glargine remained unchanged. In the transition from IV to SC insulin therapy, initial insulin glargine dose estimated as 50% of daily IV insulin requirements is adequate for patients on EN, but inadequate in those given TPN. Copyright © 2017 SEEN y SED. Publicado por Elsevier España, S.L.U. All rights reserved.
Blood glucose and plasma insulin concentrations were measured in blood sampled via a cardiac catheter in freely moving rats. To obtain a rapid conditioned cephalic phase of insulin secretion, rats were habituated to one of two feeding schedules. Clock-activated opening of doors in front of the food
Madsbad, S; Gluud, C; Bennett, Patrick
Plasma concentrations of testosterone, androstenedione and dihydrotestosterone were measured in 15 Type 1 (insulin-dependent) diabetics with (n = 8) and without (n = 7) B-cell function during 12 h of insulin withdrawal and compared with those of 8 normal subjects. Before insulin withdrawal...... the patients without B-cell function were more metabolically decompensated from after 4 h of insulin withdrawal compared with patients with B-cell function, no significant differences were found in androgen concentrations between the two groups although a tendency to lower concentrations were seen in the group...... without B-cell function....
induce several diseases associated with oxidative damage, an endemic fatal cardiomyopathy in Keshan, China (Yang. Selenium acts as an insulin-like molecule for the down-regulation of diabetic symptoms via endoplasmic reticulum stress and insulin signalling proteins in diabetes-induced non-obese diabetic mice.
Francis, A J; Home, P D; Hanning; Alberti, K G; Tunbridge, W M
Six C-peptide deficient diabetics receiving twice daily mixtures of short and intermediate acting insulins were selected for study because of persistently raised blood glucose concentrations before and after breakfast...
Zhu, Dan; Xie, Li; Kang, Youhou; Dolai, Subhankar; Bondo Hansen, Jakob; Qin, Tairan; Xie, Huanli; Liang, Tao; Rubin, Deborah C; Osborne, Lucy; Gaisano, Herbert Y
Of the four syntaxins specialized for exocytosis, syntaxin (Syn)-2 is the least understood. In this study, we used Syn-2/epimorphin knockout mice to examine the role of Syn-2 in insulin secretory granule (SG) exocytosis. Unexpectedly, Syn-2 knockout mice exhibited paradoxical superior glucose homeostasis resulting from an enhanced insulin secretion. This was confirmed in vitro by pancreatic islet perifusion showing an amplified biphasic glucose-stimulated insulin secretion arising from an increase in size of the readily releasable pool of insulin SGs and enhanced SG pool refilling. The increase in insulin exocytosis was attributed mainly to an enhanced recruitment of the larger pool of newcomer SGs that undergoes no residence time on plasma membrane before fusion and, to a lesser extent, also the predocked SGs. Consistently, Syn-2 depletion resulted in a stimulation-induced increase in abundance of exocytotic complexes we previously demonstrated as mediating the fusion of newcomer SGs (Syn-3/VAMP8/SNAP25/Munc18b) and predocked SGs (Syn-1A/VAMP2/SNAP25/Muncn18a). This work is the first to show in mammals that Syn-2 could function as an inhibitory SNARE protein that, when relieved, could promote exocytosis in pancreatic islet β-cells. Thus, Syn-2 may serve as a potential target to treat diabetes. © 2017 by the American Diabetes Association.
Ling, Ming-Hung; Chen, Mei-Chin
This study presents a dissolving microneedle patch, composed of starch and gelatin, for the rapid and efficient transdermal delivery of insulin. The microneedles completely dissolve after insertion into the skin for 5 min, quickly releasing their encapsulated payload into the skin. A histological examination shows that the microneedles have sufficient mechanical strength to be inserted in vitro into porcine skin to a depth of approximately 200 μm and in vivo into rat skin to 200-250 μm depth. This penetration depth does not induce notable skin irritation or pain sensation. To evaluate the feasibility of using these dissolving microneedles for diabetes treatment insulin-loaded microneedles were administered to diabetic rats using a homemade applicator. Pharmacodynamic and pharmacokinetic results show a similar hypoglycemic effect in rats receiving insulin-loaded microneedles and a subcutaneous injection of insulin. The relative pharmacological availability and relative bioavailability of insulin were both approximately 92%, demonstrating that insulin retains its pharmacological activity after encapsulation and release from the microneedles. Storage stability analysis confirms that more than 90% of the insulin remained in the microneedles even after storage at 25 or 37°C for 1 month. These results confirm that the proposed starch/gelatin microneedles enable stable encapsulation of bioactive molecules and have great potential for transdermal delivery of protein drugs in a relatively painless, rapid, and convenient manner. Copyright © 2013 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
Eskens, Bart J M; Mooij, Hans L; Cleutjens, Jack P M; Roos, Jozef M A; Cobelens, Johanna E; Vink, Hans; Vanteeffelen, Jurgen W G E
It has been demonstrated that insulin-mediated recruitment of microvascular blood volume is associated with insulin sensitivity. We hypothesize that insulin rapidly stimulates penetration of red blood cells (RBC) and plasma into the glycocalyx and thereby promotes insulin-mediated glucose uptake by increasing intracapillary blood volume. Experiments were performed in rats; the role of the glycocalyx was assessed by enzymatic degradation using a bolus of hyaluronidase. First, the effect of insulin on glycocalyx accessibility was assessed by measuring the depth of penetration of RBCs into the glycocalyx in microvessels of the gastrocnemius muscle with Sidestream Dark-field imaging. Secondly, peripheral insulin sensitivity was determined using intravenous insulin tolerance tests (IVITT). In addition, in a smaller set of experiments, intravital microscopy of capillary hemodynamics in cremaster muscle and histological analysis of the distribution of fluorescently labeled 40 kDa dextrans (D40) in hindlimb muscle was used to evaluate insulin-mediated increases in capillary blood volume. Insulin increased glycocalyx penetration of RBCs by 0.34±0.44 µm (Pglucose disposal compared to control rats. Insulin-mediated increases in capillary blood volume were reflected by a rapid increase in capillary tube hematocrit from 21.1±10.1% to 29.0±9.8% (Pblood in muscle, and this is associated with an increased blood volume in individual capillaries. Hyaluronidase treatment of the glycocalyx abolishes the effects of insulin on capillary blood volume and impairs insulin-mediated glucose disposal.
Full Text Available Premix insulins are commonly used insulin preparations, which are available in varying ratios of different molecules. These drugs contain one short- or rapid-acting, and one intermediate- or long-acting insulin. High-mix insulins are mixtures of insulins that contain 50% or more than 50% of short-acting insulin. This review describes the clinical pharmacology of high-mix insulins, including data from randomized controlled trials. It suggests various ways, in which high-mix insulin can be used, including once daily, twice daily, thrice daily, hetero-mix, and reverse regimes. The authors provide a rational framework to help diabetes care professionals, identify indications for pragmatic high-mix use.
Pawaskar, Manjiri D; Blickensderfer, Amy L; Hoogwerf, Byron J; Quimbo, Ralph; Wade, Rolin
The objective of this study was to examine the frequency of hypoglycemia among patients with type 2 diabetes who had concomitantly used exenatide BID (exenatide) and long-acting insulin and continued this combination vs those who continued long-acting insulin alone. Retrospective analyses, using a large managed care database, were used to estimate the frequency of hypoglycemia (episodes/patient/6 months) for patients who concomitantly used exenatide and long-acting insulin during a 6-month follow-up period. From among 2082 patients on concomitant exenatide and long-acting insulin, those who continued this combination (n=472) had a lower frequency of hypoglycemia compared to those who remained on long-acting insulin alone (n=312) (0.03 ± 1.9 vs 0.10 ± 1.01 [episodes/patient/6 months]; pdata availability. Patients who concomitantly used exenatide BID and long-acting insulin experienced a lower rate of hypoglycemia.
Full Text Available The causes of insulin resistance are not well-understood in either type 1 or type 2 diabetes. Insulin (INS is known to undergo rapid non-enzymatic covalent conjugation to glucose or other sugars (glycation. Because the insulin receptor (IR has INS-like regions associated with both glucose and INS binding, we hypothesize that hyperglycemic conditions may rapidly glycate the IR, chronically interfering with INS binding. IR peptides were synthesized spanning IR- associated INS-binding regions. Glycation rates of peptides under hyperglycemic conditions were followed over six days using matrix assisted laser desorption/ionization-time of flight (MALDI-TOF mass spectrometry. INS conjugated to horse-radish peroxidase was used to determine INS binding to IR peptides in glycated and non-glycated forms. Several IR peptides were glycated up to 14% within days of exposure to 20–60 mM glucose. Rates of IR-peptide glycation were comparable to those of insulin. Glycation of four IR peptides significantly inhibits INS binding to them. Glycation of intact IR also decreases INS binding by about a third, although it was not possible to confirm the glycation sites on the intact IR. Glycation of the IR may therefore provide a mechanism by which INS resistance develops in diabetes. Demonstration of glycation of intact IR in vivo is needed.
... Information by Audience For Women Women's Health Topics Insulin Share Tweet Linkedin Pin it More sharing options ... medicines. You can do it. Back to Top Insulin Safety Tips Never drink insulin. Do not share ...
de Courten Maximilian
Full Text Available Abstract Background In order to improve the health of people with Type 1 diabetes in developing countries, a clear analysis of the constraints to insulin access and diabetes care is needed. We developed a Rapid Assessment Protocol for Insulin Access, comprising a series of questionnaires as well as a protocol for the gathering of other data through site visits, discussions, and document reviews. Methods The Rapid Assessment Protocol for Insulin Access draws on the principles of Rapid Assessment Protocols which have been developed and implemented in several different areas. This protocol was adapted through a thorough literature review on diabetes, chronic condition management and medicine supply in developing countries. A visit to three countries in sub-Saharan Africa and meetings with different experts in the field of diabetes helped refine the questionnaires. Following the development of the questionnaires these were tested with various people familiar with diabetes and/or healthcare in developing countries. The Protocol was piloted in Mozambique then refined and had two further iterations in Zambia and Mali. Translations of questionnaires were made into local languages when necessary, with back translation to ensure precision. Results In each country the protocol was implemented in 3 areas – the capital city, a large urban centre and a predominantly rural area and their respective surroundings. Interviews were carried out by local teams trained on how to use the tool. Data was then collected and entered into a database for analysis. Conclusion The Rapid Assessment Protocol for Insulin Access was developed to provide a situational analysis of Type 1 diabetes, in order to make recommendations to the national Ministries of Health and Diabetes Associations. It provided valuable information on patients' access to insulin, syringes, monitoring and care. It was thus able to sketch a picture of the health care system with regards to its ability to
Full Text Available Environmental factors, such as the macronutrient composition of the diet, can have a profound impact on risk of diabetes and metabolic syndrome. In the present study we demonstrate how a single, simple dietary factor--leucine--can modify insulin resistance by acting on multiple tissues and at multiple levels of metabolism. Mice were placed on a normal or high fat diet (HFD. Dietary leucine was doubled by addition to the drinking water. mRNA, protein and complete metabolomic profiles were assessed in the major insulin sensitive tissues and serum, and correlated with changes in glucose homeostasis and insulin signaling. After 8 weeks on HFD, mice developed obesity, fatty liver, inflammatory changes in adipose tissue and insulin resistance at the level of IRS-1 phosphorylation, as well as alterations in metabolomic profile of amino acid metabolites, TCA cycle intermediates, glucose and cholesterol metabolites, and fatty acids in liver, muscle, fat and serum. Doubling dietary leucine reversed many of the metabolite abnormalities and caused a marked improvement in glucose tolerance and insulin signaling without altering food intake or weight gain. Increased dietary leucine was also associated with a decrease in hepatic steatosis and a decrease in inflammation in adipose tissue. These changes occurred despite an increase in insulin-stimulated phosphorylation of p70S6 kinase indicating enhanced activation of mTOR, a phenomenon normally associated with insulin resistance. These data indicate that modest changes in a single environmental/nutrient factor can modify multiple metabolic and signaling pathways and modify HFD induced metabolic syndrome by acting at a systemic level on multiple tissues. These data also suggest that increasing dietary leucine may provide an adjunct in the management of obesity-related insulin resistance.
Scattolini, Valentina; Luni, Camilla; Zambon, Alessandro; Galvanin, Silvia; Gagliano, Onelia; Ciubotaru, Catalin Dacian; Avogaro, Angelo; Mammano, Fabio; Elvassore, Nicola; Fadini, Gian Paolo
Epidemiological studies suggest that statins may promote the development or exacerbation of diabetes, but whether this occurs through inhibition of insulin secretion is unclear. This lack of understanding is partly due to the cellular models used to explore this phenomenon (cell lines or pooled islets), which are non-physiologic and have limited clinical transferability. Here, we study the effect of simvastatin on insulin secretion using single-islet cultures, an optimal compromise between biological observability and physiologic fidelity. We develop and validate a microfluidic device to study single-islet function ex vivo, which allows for switching between media of different compositions with a resolution of seconds. In parallel, fluorescence imaging provides real-time analysis of the membrane voltage potential, cytosolic Ca2+ dynamics, and insulin release during perfusion under 3 or 11 mM glucose. We found that simvastatin reversibly inhibits insulin secretion, even in high-glucose. This phenomenon is very rapid (<60 s), occurs without affecting Ca2+ concentrations, and is likely unrelated to cholesterol biosynthesis and protein isoprenylation, which occur on a time span of hours. Our data provide the first real-time live demonstration that a statin inhibits insulin secretion in intact islets and that single islets respond differently from cell lines on a short time scale. University of Padova, EASD Foundation.
Beran, David; Yudkin, John S; de Courten, Maximilian
In order to improve the health of people with Type 1 diabetes in developing countries, a clear analysis of the constraints to insulin access and diabetes care is needed. We developed a Rapid Assessment Protocol for Insulin Access, comprising a series of questionnaires as well as a protocol for th...
Hilsted, J; Madsbad, Sten; Hvidberg, A
randomized trial. During both treatment periods the patients were treated with intermediate-acting insulin at bedtime. Six of the patients were withdrawn from the study during intranasal insulin therapy due to metabolic dysregulation. Serum insulin concentrations increased more rapidly and decreased more...
Miyata, Y; Hoshi, M; Koyasu, S; Kadowaki, T; Kasuga, M; Yahara, I; Nishida, E; Sakai, H
Effects of growth factors on fluid-phase endocytosis and exocytosis in human epidermoid carcinoma KB cells were examined by measuring horseradish peroxidase (HRP) as a marker. Insulin, insulin-like growth factor-I (IGF-I), and epidermal growth factor (EGF) promoted HRP accumulation. They also stimulated the efflux of the preloaded HRP from the cells. From these results it follows that these growth factors stimulate the influx as well as the efflux of HRP, because the accumulation rate is the sum of the influx rate and the efflux rate. The stimulation of both HRP accumulation and HRP efflux was rapidly induced within 2-4 min of the addition of growth factors and persisted for at least 60 min. The concentrations eliciting half-maximal stimulatory effects of insulin, IGF-I, and EGF were about 5 X 10(-7), 1 X 10(-9), and 5 X 10(-10) M, respectively. aIR-3 (anti-type I IGF receptor antibody) completely blocked the stimulation of HRP accumulation by IGF-I but very slightly inhibited the stimulation by insulin. The 528 IgG (anti-EGF receptor antibody) inhibited the stimulation of HRP accumulation by EGF. These results indicated that each of these growth factors stimulates the HRP accumulation mediated by the corresponding (homologous) growth factor receptors. The rapid stimulation of fluid-phase influx and efflux may constitute one of the common early cellular responses to growth factors.
Callesen, Nicoline F; Mathiesen, Jonathan Michael; Ringholm, Lene
Objective: To compare glycaemic control and pregnancy outcome in women with type 1 diabetes treated with the long-acting insulin analogues detemir or glargine. Methods: Retrospective study of singleton pregnancies from 2007 to 2011 in women with type 1 diabetes with a single living fetus at 22 we...
As obesity and diabetes reach epidemic proportions in the developed world, the role of insulin resistance and its consequences are gaining prominence. Understanding the role of insulin in wide-ranging physiological processes and the influences on its synthesis and secretion, alongside its actions from the molecular to the whole body level, has significant implications for much chronic disease seen in Westernised populations today. This review provides an overview of insulin, its history, structure, synthesis, secretion, actions and interactions followed by a discussion of insulin resistance and its associated clinical manifestations. Specific areas of focus include the actions of insulin and manifestations of insulin resistance in specific organs and tissues, physiological, environmental and pharmacological influences on insulin action and insulin resistance as well as clinical syndromes associated with insulin resistance. Clinical and functional measures of insulin resistance are also covered. Despite our incomplete understanding of the complex biological mechanisms of insulin action and insulin resistance, we need to consider the dramatic social changes of the past century with respect to physical activity, diet, work, socialisation and sleep patterns. Rapid globalisation, urbanisation and industrialisation have spawned epidemics of obesity, diabetes and their attendant co-morbidities, as physical inactivity and dietary imbalance unmask latent predisposing genetic traits. PMID:16278749
Cassaglia, Priscila A; Hermes, Sam M; Aicher, Sue A; Brooks, Virginia L
Although the central effects of insulin to activate the sympathetic nervous system and enhance baroreflex gain are well known, the specific brain site(s) at which insulin acts has not been identified. We tested the hypotheses that (1) the paraventricular nucleus of the hypothalamus (PVN) and the arcuate nucleus (ArcN) are necessary brain sites and (2) insulin initiates its effects directly in the PVN and/or the ArcN. In α-chloralose anaesthetised female Sprague–Dawley rats, mean arterial pressure (MAP), heart rate (HR) and lumbar sympathetic nerve activity (LSNA) were recorded continuously, and baroreflex gain of HR and LSNA were measured before and during a hyperinsulinaemic–euglycaemic clamp. After 60 min, intravenous infusion of insulin (15 mU kg−1 min−1), but not saline, significantly increased (P musimol) of the PVN (LSNA to 124 ± 8.8% control; LSNA gain to 3.9 ± 1.7% control mmHg−1) or of the ArcN (LSNA in % control: from 100 ± 0 to 198 ± 24 (insulin), then 133 ± 23 (muscimol) LSNA gain in % control mmHg−1: from 3.9 ± 0.3 to 8.9 ± 0.9 (insulin), then 5.1 ± 0.5 (muscimol)). While insulin receptor immunoreactivity was identified in neurons in pre-autonomic PVN subnuclei, microinjection of insulin (0.6, 6 and 60 nU) into the PVN failed to alter LSNA or LSNA gain. However, ArcN insulin increased (P < 0.05) basal LSNA (in % control to 162 ± 19, 0.6 nU; 193 ± 19, 6 nU; and 205 ± 28, 60 nU) and LSNA baroreflex gain (in % control mmHg−1 from 4.3 ± 1.2 to 6.9 ± 1.0, 0.6 nU; 7.7 ± 1.2, 6 nU; and 7.8 ± 1.3, 60 nU). None of the treatments altered MAP, HR, or baroreflex control of HR. Our findings identify the ArcN as the site at which insulin acts to activate the sympathetic nervous system and increase baroreflex gain, via a neural pathway that includes the PVN.
Clausen, Trine Schnedler; Kaastrup, Peter; Stallknecht, Bente
BACKGROUND: Insertion of an insulin catheter for continuous subcutaneous insulin infusion into the subcutaneous adipose tissue (SAT) causes a tissue trauma that may have consequences for insulin absorption. We evaluated the importance of insulin catheter wear-time on subcutaneous adipose tissue...... blood flow (ATBF) and absorption of the rapid-acting insulin analog insulin aspart over a period of 4 days. METHODS: Teflon insulin catheters (Medtronic, Minneapolis, MN) were inserted into the abdominal SAT of 10 healthy men without diabetes (mean +/- SEM age, 23.0 +/- 1.1 years; body mass index, 22...
Full Text Available Heather Ulrich1,4, Benjamin Snyder1,Satish K Garg1,2,31Barbara Davis Center for Childhood Diabetes; 2Department of Medicine; 3Pediatrics; 4Department of Clinical Pharmacy, School of Pharmacy, University of Colorado at Denver and Health Sciences Center, Denver, CO, USAAbstract: Normalization of blood glucose is essential for the prevention of diabetes mellitus (DM-related microvascular and macrovascular complications. Despite substantial literature to support the benefits of glucose lowering and clear treatment targets, glycemic control remains suboptimal for most people with DM in the United States. Pharmacokinetic limitations of conventional insulins have been a barrier to achieving treatment targets secondary to adverse effects such as hypoglycemia and weight gain. Recombinant DNA technology has allowed modification of the insulin molecule to produce insulin analogues that overcome these pharmacokinetic limitations. With time action profiles that more closely mimic physiologic insulin secretion, rapid acting insulin analogues (RAAs reduce post-prandial glucose excursions and hypoglycemia when compared to regular human insulin (RHI. Insulin glulisine (Apidra® is a rapid-acting insulin analogue created by substituting lysine for asparagine at position B3 and glutamic acid for lysine at position B29 on the B chain of human insulin. The quick absorption of insulin glulisine more closely reproduces physiologic first-phase insulin secretion and its rapid acting profile is maintained across patient subtypes. Clinical trials have demonstrated comparable or greater efficacy of insulin glulisine versus insulin lispro or RHI, respectively. Efficacy is maintained even when insulin glulisine is administered post-meal. In addition, glulisine appears to have a more rapid time action profile compared with insulin lispro across various body mass indexes (BMIs. The safety and tolerability profile of insulin glulisine is also comparable to that of insulin
Tsuneki, Hiroshi; Yoshida, Hitomi; Endo, Kosuke; Mori, Norihiko; Hosoh, Shuji; Tsuda, Masaaki; Wada, Tsutomu; Sasaoka, Toshiyasu
Centrally administered insulin improves cognitive functions in patients with Alzheimer's disease; however, it remains unknown whether long-acting insulin analogs exert more pronounced effects than insulin. In the present study, we directly compared the effects of insulin and its analogs on neural functions in vitro and in vivo. Cultured rat cerebral cortical neurons were treated with insulin, insulin glargine U100 (Gla), insulin detemir (Det), or insulin degludec (Deg). Moreover, these drugs were intracerebroventricularly administered to mice. Their efficacies were evaluated by biochemical and behavioral analyses. In cultured neurons, insulin, Gla, and Det increased phosphorylation of Akt and enhanced gene expression of brain-derived neurotrophic factor to a similar extent, although Deg was less effective. The effects of Det and Deg, but not insulin and Gla were suppressed by addition of albumin. When the drug was centrally administered, the increasing effects of insulin on the Akt phosphorylation were comparable to those of Gla but greater than those of Det in hippocampus and cerebral cortex of diabetic db/db and non-diabetic db/m+ mice. Moreover, insulin and Gla enhanced memory functions in Y-maze test and suppressed depression-like behavior in forced swim test in normal mice to a similar extent, and these effects were more potent than those of Det. Insulin and Gla have greater impacts on central nervous system than insulin analogs with high albumin sensitivity, such as Det and Deg. These pharmacological profiles should be taken into account for developing an insulin-based therapy to treat Alzheimer's disease. Copyright © 2017 Elsevier B.V. All rights reserved.
Full Text Available Abstract In order to provide comprehensive information on the differences in bioactivity between human insulin and insulin analogues, published in vitro comparisons of human insulin and the rapid acting analogues insulin lispro (Humalog®, insulin aspart ( NovoRapid®, insulin glulisine (Apidra®, and the slow acting analogues insulin glargine (Lantus®, and insulin detemir (Levemir® were gathered from the past 20 years (except for receptor binding studies. A total of 50 reports were retrieved, with great heterogeneity among study methodology. However, various differences in bioactivity compared to human insulin were obvious (e.g. differences in effects on metabolism, mitogenesis, apoptosis, intracellular signalling, thrombocyte function, protein degradation. Whether or not these differences have clinical bearings (and among which patient populations remains to be determined.
Engwerda, E.E.; Tack, C.J.; Galan, B.E. de
AIMS: Rapid-acting insulin analogues are generally preferred over regular human insulin because of their more immediate onset of action and shorter time-action profile. However, these analogues may not always be tolerated by or universally available for people with insulin-requiring diabetes. Jet
Broussard, Josiane L; Nelson, Michael D; Kolka, Cathryn M; Bediako, Isaac Asare; Paszkiewicz, Rebecca L; Smith, Laura; Szczepaniak, Edward W; Stefanovski, Darko; Szczepaniak, Lidia S; Bergman, Richard N
The worldwide incidence of obesity and diabetes continues to rise at an alarming rate. A major cause of the morbidity and mortality associated with obesity and diabetes is heart disease, yet the mechanisms that lead to cardiovascular complications remain unclear. We performed cardiac MRI to assess left ventricular morphology and function during the development of moderate obesity and insulin resistance in a well-established canine model (n = 26). To assess the influence of dietary fat composition, we randomised animals to a traditional lard diet (rich in saturated and monounsaturated fat; n = 12), a salmon oil diet (rich in polyunsaturated fat; n = 8) or a control diet (n = 6). High-fat feeding with lard increased body weight and fasting insulin and markedly reduced insulin sensitivity. Lard feeding also significantly reduced left ventricular function, evidenced by a worsening of circumferential strain and impairment in left ventricular torsion. High-fat feeding with salmon oil increased body weight; however, salmon oil feeding did not impair insulin sensitivity or cardiac function. These data emphasise the importance of dietary fat composition on both metabolic and cardiac function, and have important implications for the relationship between diet and health.
Bonen, Arend; Jain, Swati S; Snook, Laelie A; Han, Xiao-Xia; Yoshida, Yuko; Buddo, Kathryn H; Lally, James S; Pask, Elizabeth D; Paglialunga, Sabina; Beaudoin, Marie-Soleil; Glatz, Jan F C; Luiken, Joost J F P; Harasim, Ewa; Wright, David C; Chabowski, Adrian; Holloway, Graham P
The mechanisms for diet-induced intramyocellular lipid accumulation and its association with insulin resistance remain contentious. In a detailed time-course study in rats, we examined whether a high-fat diet increased intramyocellular lipid accumulation via alterations in fatty acid translocase (FAT/CD36)-mediated fatty acid transport, selected enzymes and/or fatty acid oxidation, and whether intramyocellular lipid accretion coincided with the onset of insulin resistance. We measured, daily (on days 1-7) and/or weekly (for 6 weeks), the diet-induced changes in circulating substrates, insulin, sarcolemmal substrate transporters and transport, selected enzymes, intramyocellular lipids, mitochondrial fatty acid oxidation and basal and insulin-stimulated sarcolemmal GLUT4 and glucose transport. We also examined whether upregulating fatty acid oxidation improved glucose transport in insulin-resistant muscles. Finally, in Cd36-knockout mice, we examined the role of FAT/CD36 in intramyocellular lipid accumulation, insulin sensitivity and diet-induced glucose intolerance. Within 2-3 days, diet-induced increases occurred in insulin, sarcolemmal FAT/CD36 (but not fatty acid binding protein [FABPpm] or fatty acid transporter [FATP]1 or 4), fatty acid transport and intramyocellular triacylglycerol, diacylglycerol and ceramide, independent of enzymatic changes or muscle fatty acid oxidation. Diet-induced increases in mitochondria and mitochondrial fatty acid oxidation and impairments in insulin-stimulated glucose transport and GLUT4 translocation occurred much later (≥21 days). FAT/CD36 ablation impaired insulin-stimulated fatty acid transport and lipid accumulation, improved insulin sensitivity and prevented diet-induced glucose intolerance. Increasing fatty acid oxidation in insulin-resistant muscles improved glucose transport. High-fat feeding rapidly increases intramyocellular lipids (in 2-3 days) via insulin-mediated upregulation of sarcolemmal FAT/CD36 and fatty acid
Gupta, Vivek; Doshi, Nishit; Mitragotri, Samir
Objectives Caco-2 monolayers are one of the most widely used in vitro models for prediction of intestinal permeability of therapeutic molecules. However, the conventional Caco-2 monolayer model has several drawbacks including labor-intensive culture process, unphysiological growth conditions, lack of reproducibility and limited throughput. Here, we report on the use of 3-day Caco-2 monolayers for assessing permeability of polypeptide drugs. Methods The 3-day monolayers were grown in a commercially available transwell set-up, which facilitates rapid development of the Caco-2 monolayers in an intestinal epithelial differentiation mimicking environment. This set-up included use of serum-free medium of defined composition with supplements such as butyric acid, hormones, growth factors, and other metabolites, reported to regulate the differentiation of intestinal epithelial cells in vivo. We measured permeability of 3 different therapeutic polypeptides; insulin, calcitonin, and exenatide across the monolayer. Results Preliminary validation of the monolayer was carried out by confirming dose-dependent permeation of FITC-insulin and sulforhodamine-B. Transport of insulin, calcitonin, and exenatide measured at different loading concentrations suggests that the permeability values obtained with 3-day cultures resemble more closely the values obtained with ex vivo models compared to permeability values obtained with conventional 21-day cultures. Conclusions Short-term 3-day Caco-2 monolayers provide new opportunities for developing reproducible and high-throughput models for screening of therapeutic macromolecules for oral absorption. PMID:23483881
Heintjes, Edith M; Thomsen, Trine L; Penning-van Beest, Fernie J A; Christensen, Torsten E; Herings, Ron M C
The objective was to compare glycemic control, insulin utilization, and body weight in patients with type 2 diabetes (T2D) initiated on insulin detemir (IDet) or insulin glargine (IGlar) in a real-life setting in the Netherlands. Insulin-naïve patients with T2D, starting treatment with IDet or IGlar between January 1, 2004 and June 30, 2008, were selected from the PHARMO data network. Glycemic control (hemoglobin A1c [HbA1c]), target rates (HbA1c <7%), daily insulin dose, and weight gain were analyzed comparing IDet and IGlar for patients with available HbA1c levels both at baseline and at 1-year follow-up. Analysis of all eligible patients (AEP) and a subgroup of patients without treatment changes (WOTC) in the follow-up period were adjusted for patient characteristics, propensity scores, and baseline HbA1c. A total of 127 IDet users and 292 IGlar users were included in the WOTC analyses. The mean HbA1c dropped from 8.4%-8.6% at baseline to 7.4% after 1 year. Patients at HbA1c goal increased from 9% at baseline to 32% for IDet and 11% to 35% for IGlar, which was not significantly different (OR 0.75, 95% CI 0.46, 1.24). Weight gain (n=90) was less among IDet users (+0.4 kg) than among IGlar users (+1.1 kg), albeit not significant. The AEP analysis (252 IDet + 468 IGlar users) showed similar results with 33%-36% at goal (OR 0.81, 95% CI 0.57, 1.16), and median daily insulin doses of 25 IU/day (P=0.70). There was no significant difference between users of IDet and IGlar with respect to glycemic control and insulin dose in a real-life setting. The low proportion of patients on target at baseline may indicate that insulin therapy is initiated too late. Moreover, the observation that one-third of the patients reached HbA1c target at follow-up may indicate that basal insulin analogs are not titrated intensively enough.
... adjusting Secondary Nephropathy insulin therapy. Hyperglycemia Neuropathy Adherence to insulin therapy... MDI, which will be defined as at least three injections of basal and rapid-acting insulin per day. 2. rt-CGM would be compared with SMBG, which will be defined as at least three fingersticks per day...
Berard, Lori; MacNeill, Gail
Here, we discuss certain practical issues related to use of insulin degludec, a new long-acting basal insulin analogue. Degludec provides uniform ("peakless") action that extends over more than 24 hours and is highly consistent from dose to dose. Like the 2 previously available basal analogues (detemir and glargine), degludec is expected to simplify dose adjustment and enable patients to reach their glycemic targets with reduced risk of hypoglycemia. Phase 3 clinical trials involving type 1 and type 2 diabetes have demonstrated that degludec was noninferior to glargine in allowing patients to reach a target glycated hemoglobin (A1C) of 7%, and nocturnal hypoglycemia occurred significantly less frequently with degludec. In addition, when dosing intervals vary substantially from day to day, degludec continues to be effective and to maintain a low rate of nocturnal hypoglycemia. Degludec thus has the potential to reduce risk of nocturnal hypoglycemia, to enhance the flexibility of the dosing schedule and to improve patient and caregiver confidence in the stability of glycemic control. A dedicated injector, the FlexTouch prefilled pen, containing degludec 200 units/mL, will be recommended for most patients with type 2 diabetes. Degludec will also be available as 100 units/mL cartridges, to be used in the NovoPen 4 by patients requiring smaller basal insulin doses, including most patients with type 1 diabetes. Copyright © 2015 Canadian Diabetes Association. Published by Elsevier Inc. All rights reserved.
Macotela, Yazmin; Emanuelli, Brice; Bång, Anneli M
and at multiple levels of metabolism. Mice were placed on a normal or high fat diet (HFD). Dietary leucine was doubled by addition to the drinking water. mRNA, protein and complete metabolomic profiles were assessed in the major insulin sensitive tissues and serum, and correlated with changes in glucose...
León E Litwak
Full Text Available Hyperglycemia during hospitalization is a common condition associated with poor prognosis. To date, insulin is the best strategy to treat hyperglycemia in these patients. An adequate glycemic control is associated with better clinical results. Nevertheless, glycemic goals are still controversial due to the increase of hypoglycemia and other adverse events. Diabetes mellitus is still the main cause of chronic renal failure in our country and its treatment deserves a special analysis considering that insulin pharmacokinetics is altered. Recommendations in this setting are based in expert panel opinions, focusing mainly in intermediate or long acting insulins combined with regular insulin and/or rapid acting analogues. During pregnancy, NPH and regular insulin are safe and effective. It is worth mentioning that the development of new long and rapid acting molecules yielded lower glycemic variability, better post-prandial control and less hypoglycemia. The aim of this study is to provide a review of the proper use of insulin in these special conditions.
Full Text Available Introduction:Using rapid detection methods is important for detection of plant pathogens and also prevention through spreading pests in agriculture. Citrus brown spot disease caused by pathogenic isolates of Alternaria alternata is a common disease in Iran. Materials and methods: In this study, for the first time a PCR based molecular method was used for rapid diagnosis of brown spot disease. Nine isolates of A. Alternata were isolated in PDA medium from different citrus gardens. The plant pathogenic activity was examined in tangerine leaves for isolates. Results showed that these isolates are the agents of brown spot disease. PCR amplification of specific ACT-toxin gene was performed for DNA extracted from A. alternata isolates, with 11 different fungal isolates as negative controls and 5 DNA samples extracted from soil. Results: Results showed that A. alternata, the causal agent of brown spot disease, can be carefully distinguished from other pathogenic agents by performing PCR amplification with specific primers for ACT toxin gene. Also, the results from Nested-PCR method confirmed the primary reaction and the specificity of A. alternata for brown spot disease. PCR results to control samples of the other standard fungal isolates, showed no amplification band. In addition, PCR with the DNA extracted from contaminated soils confirmed the presence of ACT toxin gene. Discussion and conclusion: Molecular procedure presented here can be used in rapid identification and prevention of brown spot infection in citrus gardens all over the country.
Bladbjerg, Else-Marie; Henriksen, Jan Erik; Akram, Sumarra
collected at 7.40 (fasting), 9.30, 11.30, 13.30 and 15.30 and analysed for glucose, insulin, lipids, intercellular adhesion molecules (ICAM), C-reactive protein (CRP), von Willebrand factor (vWF) and fibrinogen. The postprandial glucose response differed significantly between insulin regimens......WF and fibrinogen. The rapid-acting insulin analogue aspart and the intermediate-acting insulin NPH had different effects on postprandial glucose response but similar postprandial effects on markers of inflammation and endothelial dysfunction....... Acute hyperglycaemia exerts deleterious effects on the arterial wall. We suggested that rapid-acting insulin has a beneficial postprandial effect on endothelial dysfunction and inflammation compared with intermediate-acting insulin because of its ability to lower postprandial hyperglycaemia...
Effect of long-acting testosterone treatment on functional exercise capacity, skeletal muscle performance, insulin resistance, and baroreflex sensitivity in elderly patients with chronic heart failure a double-blind, placebo-controlled, randomized study
Caminiti, Giuseppe; Volterrani, Maurizio; Iellamo, Ferdinando; Marazzi, Giuseppe; Massaro, Rosalba; Miceli, Marco; Mammi, Caterina; Piepoli, Massimo; Fini, Massimo; Rosano, Giuseppe M C
This study investigated the effect of a 12-week long-acting testosterone administration on maximal exercise capacity, ventilatory efficiency, muscle strength, insulin resistance, and baroreflex sensitivity (BRS...
Rosenfalck, A M; Thorsby, P; Kjems, L
The effect on postprandial blood glucose control of an immediately pre-meal injection of the rapid acting insulin analogue Aspart (IAsp) was compared with that of human insulin Actrapid injected immediately or 30 minutes before a test meal in insulin-treated type 2 diabetic patients with residual.......0 nmol/l (range, 0.3-2.5) and diabetes duration 12.5 years (range, 3.0-26.0). Twenty-two patients completed the study. A significantly improved postprandial glucose control was demonstrated with IAsp as compared to Act0, based on a significantly smaller postprandial blood glucose excursion (IAsp, 899......-meal administration of the rapid-acting insulin analogue Aspart in patients with type 2 diabetes resulted in an improved postprandial glucose control compared to Actrapid injected immediately before the meal, but showed similar control compared to Actrapid injected 30 minutes before the meal. These results indicate...
Szűcs, M; Vahsen, M L; Melbourne, B A; Hoover, C; Weiss-Lehman, C; Hufbauer, R A
Colonization and expansion into novel landscapes determine the distribution and abundance of species in our rapidly changing ecosystems worldwide. Colonization events are crucibles for rapid evolution, but it is not known whether evolutionary changes arise mainly after successful colonization has occurred, or if evolution plays an immediate role, governing the growth and expansion speed of colonizing populations. There is evidence that spatial evolutionary processes can speed range expansion within a few generations because dispersal tendencies may evolve upwards at range edges. Additionally, rapid adaptation to a novel environment can increase population growth rates, which also promotes spread. However, the role of adaptive evolution and the relative contributions of spatial evolution and adaptation to expansion are unclear. Using a model system, red flour beetles (Tribolium castaneum), we either allowed or constrained evolution of populations colonizing a novel environment and measured population growth and spread. At the end of the experiment we assessed the fitness and dispersal tendency of individuals originating either from the core or edge of evolving populations or from nonevolving populations in a common garden. Within six generations, evolving populations grew three times larger and spread 46% faster than populations in which evolution was constrained. Increased size and expansion speed were strongly driven by adaptation, whereas spatial evolutionary processes acting on edge subpopulations contributed less. This experimental evidence demonstrates that rapid evolution drives both population growth and expansion speed and is thus crucial to consider for managing biological invasions and successfully introducing or reintroducing species for management and conservation.
Duman, Ronald S
Stress and depression are associated with atrophy and loss of neurons in limbic and cortical brain regions that could contribute to the symptoms of depression. Typical monoamine reuptake inhibitor antidepressants have only modest efficacy and require long-term treatment, and are only weakly effective in blocking or reversing these structural changes caused by stress. Recent findings demonstrate that ketamine, an NMDA receptor antagonist, produces rapid antidepressant actions in difficult to treat depressed patients. In addition, preclinical studies demonstrate that ketamine rapidly increases synaptic connections in the prefrontal cortex by increasing glutamate signaling and activation of pathways that control the synthesis of synaptic proteins. Moreover, ketamine rapidly reverses the synaptic deficits caused by exposure to chronic stress in rodent models. Studies of the signaling mechanisms underlying the actions of ketamine have provided novel approaches and targets for new rapid acting antidepressants with decreased side effects, as well as a better understanding of the neurobiology of stress, depression, and treatment response. © 2014 Wiley Periodicals, Inc.
Huang, Jiung-Pang; Huang, Shiang-Suo; Deng, Jen-Ying; Chang, Chih-Chun; Day, Yuan-Ji; Hung, Li-Man
Resveratrol (RSV), a natural phenolic compound, has been found to display cardiovascular protective and insulin-sensitizing properties. In this study, the effects of RSV and its combination with insulin on mortality, hemodynamics, insulin signaling, and nitrosative stress were compared in streptozotocin (STZ)-induced diabetic rats with or without acute myocardial ischemia/reperfusion (I/R) injury. Under normoxic conditions, cardiac systolic and diastolic functions and insulin-mediated Akt/GLUT4 (glucose transporter 4) activation were impaired in STZ-diabetic rats. The combination of RSV and insulin significantly prevented the above diabetes-associated abnormalities. Notwithstanding that, the diabetic state rendered the animals more susceptible to myocardial I/R injury, and the mortality rate and inducible nitric oxide synthase (iNOS)/nitrotyrosine protein expression and superoxide anion production were also further increased in I/R-injured diabetic hearts. In contrast, RSV treatment alone resulted in a lower mortality rate (from 62.5 to 18%) and better cardiac systolic function than its combination with insulin. RSV also inhibited iNOS/nitrotyrosine protein overexpression and superoxide anion overproduction in I/R-injured diabetic myocardium. Hyperglycemia, impairment of insulin signaling, overexpression of iNOS/nitrotyrosine, and superoxide anion overproduction were markedly rescued by the combination treatment, which did not show an improvement in mortality rate (30%) or cardiac performance over RSV treatment alone. These results indicate that insulin and RSV synergistically prevented cardiac dysfunction in diabetes and this may be in parallel with activation of the insulin-mediated Akt/GLUT4 signaling pathway. Although activation of the protective signal (Akt/GLUT4) and suppression of the adverse markers (iNOS, nitrotyrosine, and superoxide anion) were simultaneously observed in insulin and RSV combination treatment, insulin counteracted the advantage of RSV in
Albèr, Anders; Brønden, Andreas; Knop, Filip K
, which is associated with well-described and unfortunate adverse effects such as hypoglycaemia and increased body weight. Glucagon-like peptide-1 (GLP-1) receptor agonists (RAs) are the focus of increasing interest as a possible adjunctive treatment to insulin in type 1 diabetes because......A large proportion of patients with type 1 diabetes do not reach their glycaemic target of glycated hemoglobin (HbA1c) diabetes are overweight and obese. Treatment of type 1 diabetes is based on insulin therapy...... of their glucagonostatic and extrapancreatic effects. So far, the focus has mainly been on the long-acting GLP-1RAs, but the risk-benefit ratio emerging from studies evaluating the effect of long-acting GLP-1RAs as adjunctive therapy to insulin therapy in patients with type 1 diabetes has been disappointing. This might...
Kawamura, Tomoyuki; Urakami, Tatsuhiko; Sugihara, Shigetaka; Kim, Hey Sook; Mochizuki, Mie; Amamiya, Shin
The efficacy of continuous subcutaneous insulin infusion (CSII) of the rapid-acting insulin analogue, insulin aspart, was evaluated in 26 patients with childhood-onset type 1 diabetes aged between 6 and 18 yr who had been on basal-bolus therapy (multiple daily injection (MDI) of regular human insulin or rapid-acting insulin and intermediate/long-acting insulin). The glycemic control in the patients was evaluated based on changes in the clinical parameters and the patient quality of life (QOL) was evaluated by using the insulin therapy-related QOL questionnaire. Twenty two patients continued CSII during the 6-mo study period. The mean HbA1c was 7.8 ± 1.8% at baseline and it decreased to 7.4 ± 0.8% at 6 mo after the start of the CSII. Overall, no decrease of the QOL post-CSII initiation was noted. The possible superiority of CSII as compared to MDI was suggested for patients who "eat out" or "have to look for an appropriate place for insulin injection." Aside from an inadequate indwelling needle placement detected after the initiation of CSII in several patients, no adverse event associated with NovoRapid(®) was seen. In conclusion, CSII of rapid-acting insulin appears to be a useful therapy for patients with childhood-onset type 1 diabetes.
Bladbjerg, Else-Marie; Henriksen, Je; Akram, S
), 9:30, 11:30, 13:30, and 15:30 and analysed for glucose, activated factor VII (FVIIa), D-dimer, prothrombin fragment 1+2 (F1+2), tissue plasminogen activator antigen (t-PA), and plasminogen activator inhibitor activity (PAI). Results: The postprandial glucose response differed significantly between......: The rapid-acting insulin analogue aspart and the intermediate-acting insulin NPH had similar postprandial effects on markers of coagulation activation and fibrinolysis despite different effects on postprandial glucose response.......Aims: Acute hyperglycaemia induces coagulation activation in diabetes patients. We hypothesized that rapid-acting insulin has a beneficial postprandial effect on coagulation and fibrinolysis compared with intermediate-acting insulin due to its ability to lower postprandial hyperglycaemia. Materials...
To improve insulin therapy, new insulin analogues have been developed. Two fast-acting analogues with a more rapid onset of effect and a shorter duration of action combined with a low day-to-day variation in absorption rate are now available. Despite this favourable time-action profile most studi......, the new fast-acting analogues have not achieved the expected commercial success, which emphasises the need for new strategies for basal insulin supplementation, exercise, diet and blood glucose monitoring....... in a long half-life with a residual activity of about 50% 24 h after injection. Insulin glargine is a peakless insulin and studies in both type 1 and type 2 diabetic patients indicate that glargine improves fasting blood glucose control and reduces the incidence of nocturnal hypoglycaemia. Surprisingly...
Lai Guan Ng
Full Text Available Dendritic cells (DC, including those of the skin, act as sentinels for intruding microorganisms. In the epidermis, DC (termed Langerhans cells, LC are sessile and screen their microenvironment through occasional movements of their dendrites. The spatio-temporal orchestration of antigen encounter by dermal DC (DDC is not known. Since these cells are thought to be instrumental in the initiation of immune responses during infection, we investigated their behavior directly within their natural microenvironment using intravital two-photon microscopy. Surprisingly, we found that, under homeostatic conditions, DDC were highly motile, continuously crawling through the interstitial space in a Galpha(i protein-coupled receptor-dependent manner. However, within minutes after intradermal delivery of the protozoan parasite Leishmania major, DDC became immobile and incorporated multiple parasites into cytosolic vacuoles. Parasite uptake occurred through the extension of long, highly dynamic pseudopods capable of tracking and engulfing parasites. This was then followed by rapid dendrite retraction towards the cell body. DDC were proficient at discriminating between parasites and inert particles, and parasite uptake was independent of the presence of neutrophils. Together, our study has visualized the dynamics and microenvironmental context of parasite encounter by an innate immune cell subset during the initiation of the immune response. Our results uncover a unique migratory tissue surveillance program of DDC that ensures the rapid detection of pathogens.
Diabetes is a chronic, debilitating disease that afflicts millions of people worldwide and poor glycemic control in this disease leads to numerous microvascular and macrovascular complications. There is growing evidence that tight glycemic control prevents the development, and delays the progression, of microvascular complications and possibly macrovascular disease in patients with diabetes. All patients with Type 1 diabetes and many patients with Type 2 diabetes require intensive insulin therapy to achieve optimal glucose control. Although subcutaneous insulin therapy is the mainstay of insulin therapy, there are patients who fear needles and often refuse to start insulin therapy despite suboptimal glucose control. In these patients, inhaled insulin represents a non-invasive, painless method to administer intensive insulin treatment. The Novo Nordisk AS AERx iDMS (insulin Diabetes Management System) for inhaled insulin is a novel device that administers an aerosol of liquid insulin into the deep lung with dose adjustments as precise as one subcutaneous unit. Initial pharmacokinetic and pharmacodynamic studies demonstrate that the device delivers liquid insulin in a clear dose-response manner and with a rapid onset of action similar to the fast-acting analog insulins. At present, large, long-term Phase III studies are in progress to document not only the efficacy, but also the safety and feasibility of this device in the treatment of patients with diabetes.
Lehmann, Eldon D.; Tarín, Cristina; Bondia, Jorge; Teufel, Edgar; Deutsch, Tibor
Introduction AIDA is an interactive educational diabetes simulator that has been available without charge via the Internet for over 12 years. Recent articles have described the incorporation of a novel generic model of insulin absorption into AIDA as a way of enhancing its capabilities. The basic model components to be integrated have been overviewed, with the aim being to provide simulations of regimens utilizing insulin analogues, as well as insulin doses greater than 40 IU (the current upper limit within the latest release of AIDA [v4.3a]). Some preliminary calculated insulin absorption results have also recently been described. Methods This article presents the first simulated plasma insulin profiles from the integration of the generic subcutaneous insulin absorption model, and the currently implemented model in AIDA for insulin disposition. Insulin absorption has been described by the physiologically based model of Tarín and colleagues. A single compartment modeling approach has been used to specify how absorbed insulin is distributed in, and eliminated from, the human body. To enable a numerical solution of the absorption model, a spherical subcutaneous depot for the injected insulin dose has been assumed and spatially discretized into shell compartments with homogeneous concentrations, having as its center the injection site. The number of these compartments will depend on the dose and type of insulin. Insulin inflow arises as the sum of contributions to the different shells. For this report the first bench testing of plasma insulin determinations has been done. Results Simulated plasma insulin profiles are provided for currently available insulin preparations, including a rapidly acting insulin analogue (e.g., lispro/Humalog or aspart/Novolog), a short-acting (regular) insulin preparation (e.g., Actrapid), intermediate-acting insulins (both Semilente and neutral protamine Hagedorn types), and a very long-acting insulin analogue (e.g., glargine/Lantus), as
Menting, John G; Gajewiak, Joanna; MacRaild, Christopher A; Chou, Danny Hung-Chieh; Disotuar, Maria M; Smith, Nicholas A; Miller, Charleen; Erchegyi, Judit; Rivier, Jean E; Olivera, Baldomero M; Forbes, Briony E; Smith, Brian J; Norton, Raymond S; Safavi-Hemami, Helena; Lawrence, Michael C
Insulins in the venom of certain fish-hunting cone snails facilitate prey capture by rapidly inducing hypoglycemic shock. One such insulin, Conus geographus G1 (Con-Ins G1), is the smallest known insulin found in nature and lacks the C-terminal segment of the B chain that, in human insulin, mediates engagement of the insulin receptor and assembly of the hormone's hexameric storage form. Removal of this segment (residues B23-B30) in human insulin results in substantial loss of receptor affinity. Here, we found that Con-Ins G1 is monomeric, strongly binds the human insulin receptor and activates receptor signaling. Con-Ins G1 thus is a naturally occurring B-chain-minimized mimetic of human insulin. Our crystal structure of Con-Ins G1 reveals a tertiary structure highly similar to that of human insulin and indicates how Con-Ins G1's lack of an equivalent to the key receptor-engaging residue PheB24 is mitigated. These findings may facilitate efforts to design ultrarapid-acting therapeutic insulins.
Subhash Kumar Wangnoo
Full Text Available The primary clinical goals to be achieved with insulin initiation are elimination of ketosis and hyperglycemia with prevention of chronic complications. Insulin therapy is the mainstay in management of type 1 diabetes, which should be aimed at achieving good glycemic control, with achievement of hemoglobin A1c (HbA1c <7.5%, pre-meal self-monitored blood glucose (SMBG of 90-130 mg/dL, bed time SMBG of 100-140 mg/dL, mean blood glucose level of 120-160 mg/dL and no ketonuria. Two classes of insulin are available for use in T1DM viz. bolus/prandial insulins (rapid-acting insulins and short-acting insulins and basal insulins (intermediate-acting insulin and long-acting insulin. Insulin glargine and glulisine can be used in children above 6 years, lispro in children above 3 years and detemir and aspart in children above 2 years. The caution for hypoglycemia should be exercised while prescribing them. Degludec is currently not approved for pediatric use. The initial insulin regimen should comprise of ≥2 daily bolus and ≥1 basal insulin injections. Insulin intensification would be required if the initial regimen fails, which can be achieved by increasing frequency of long and rapid acting insulin analogues. The American Diabetes Association guidelines recommend HbA1c targets of <8.0% for children <6 years of age, ≤7.5% for children 6 to 12 years of age, and ≤7.0% for adolescents, 12-18 years of age. However, the evidence is now in favor of a single target HbA1c of ≤7.5% for all children and adolescents <19 years of age.
Full Text Available Objective: To better understand exenatide’s role in the treatment of type 2 diabetes, this analysis assessed its cost-effectiveness in comparison to an intermediate (NPH and long-acting insulin (glargine. Exenatide is a recently approved medication for the treatment of type 2 diabetes for use in addition to frequently used oral diabetes medications. Methods: Two studies were identified by a Medline search (1996-Oct 2005 that were similar in study duration, baseline glycemic control, population size, and primary outcomes to appropriately assess the cost-effectiveness of either insulin in comparison to exenatide on both glycemic and weight control. Results: Both NPH and glargine appear to be more cost effective than exenatide with respect to glycemic control (incremental CE ratios -1,968 and -65,520 respectively. Exenatide appears to be more cost effective for reductions in body weight than either NPH (CE ratio 235 or glargine (CE ratio 128. Conclusions Compared to intermediate and long-acting insulin therapies, exenatide does not appear to be as cost effective for the treatment of type 2 diabetes.
Sanlioglu, Ahter D.; Altunbas, Hasan Ali; Balci, Mustafa Kemal; Griffith, Thomas S.; Sanlioglu, Salih
Diabetes is a pandemic disease characterized by autoimmune, genetic and metabolic abnormalities. While insulin deficiency manifested as hyperglycemia is a common sequel of both Type-1 and Type-2 diabetes (T1DM and T2DM), it does not result from a single genetic defect—rather insulin deficiency results from the functional loss of pancreatic β cells due to multifactorial mechanisms. Since pancreatic β cells of patients with T1DM are destroyed by autoimmune reaction, these patients require daily insulin injections. Insulin resistance followed by β cell dysfunction and β cell loss is the characteristics of T2DM. Therefore, most patients with T2DM will require insulin treatment due to eventual loss of insulin secretion. Despite the evidence of early insulin treatment lowering macrovascular (coronary artery disease, peripheral arterial disease and stroke) and microvascular (diabetic nephropathy, neuropathy and retinopathy) complications of T2DM, controversy exists among physicians on how to initiate and intensify insulin therapy. The slow acting nature of regular human insulin makes its use ineffective in counteracting postprandial hyperglycemia. Instead, recombinant insulin analogs have been generated with a variable degree of specificity and action. Due to the metabolic variability among individuals, optimum blood glucose management is a formidable task to accomplish despite the presence of novel insulin analogs. In this article, we present a recent update on insulin analog structure and function with an overview of the evidence on the various insulin regimens clinically used to treat diabetes. PMID:23584214
Cengiz, Eda; Weinzimer, Stuart A.; Sherr, Jennifer L.; Tichy, Eileen; Martin, Melody; Carria, Lori; Steffen, Amy; Tamborlane, William V.
Background and Objective Subcutaneously injected rapid-acting insulin analogs do not replicate physiologic insulin action due to delays in their onset and peak action resulting in post-prandial glucose excursions. The InsuPatch (IP) is a novel insulin infusion site warming device developed to accelerate insulin action by increasing blood flow to the area of insulin absorption. 13 adolescents with type 1 diabetes (mean age 14±4 years) were enrolled in this study to investigate the effect of the IP on the pharmacodynamics and pharmacokinetics of a 0.2u/kg bolus dose of aspart insulin using the euglycemic clamp technique. Research Design and Methods Each subject underwent two euglycemic clamp procedures on separate occasions: one with and one without IP activation in random order. Results When the insulin bolus was given with IP activation as compared to without IP activation, time to reach maximum insulin action (TGIRmax) and to reach 50% maximum action (T 50%GIRmax) were 35 and 18 minutes earlier (125±8 min vs. 90±6min, p=0.002 and 58±5min. vs. 40±3min, p=0.01, respectively), and the AUC GIR 0-90min, reflecting early glucodynamic action, was significantly greater (p=0.001). IP activation also accelerated the rise in plasma insulin levels after the bolus (p=0.03) and resulted in a higher peak (p=0.04) and greater overall increase (p=0.02) in plasma insulin levels. Conclusions Our results demonstrate that insulin infusion site warming with IP activation accelerates the time action profile of aspart insulin which may be of benefit to current open-loop and future closed-loop insulin delivery in patients with type 1 diabetes. PMID:23107353
Muñoz Torres, Manuel
Degludec is the most recent molecule of the ultra-long-acting basal insulin analogues approved for human use. It forms soluble multihexamers which after subcutaneous injection are converted into monomers, and are thus slowly and continuously absorbed into the bloodstream. This absorption mechanism confers degludec an ultra-long and stable action profile, with no concentration peaks. This paper discusses the most recent studies in patients with type 1 and 2 diabetes mellitus, which showed degludec to be non inferior in decreasing HbA1c, ensuring optimum glycemic control similar to that achieved with insulin glargine or detemir. Degludec also had an improved safety profile, as it was associated to a significantly lower rate of nocturnal hypoglycemia in both types of diabetes and to a potentially lower overall hypoglycemia rate in type 2 DM. Degludec also opens the possibility to use more flexible regimens. Copyright © 2013 SEEN. Published by Elsevier Espana. All rights reserved.
Ortis, Fernanda; Cardozo, Alessandra K; Crispim, Daisy
Cytokines, such as IL-1beta and TNF-alpha, contribute to pancreatic beta-cell death in type 1 diabetes mellitus. The transcription factor nuclear factor-kappaB (NF-kappaB) mediates cytokine-induced beta-cell apoptosis. Paradoxically, NF-kappaB has mostly antiapoptotic effects in other cell types......-kappaB activation in insulin-producing cells is more rapid, marked, and sustained than in fibroblasts, which correlates with a more pronounced activation of downstream genes and a proapoptotic outcome....
The predominant number of papers published from the middle of 2009 to the middle of 2010 about alternative routes of insulin administration (ARIA) were still about inhaled insulin. Long-term experience with Exubera was the topic of a number of publications that are also of relevance for inhaled insulin in general. The clinical trials performed with AIR insulin by Eli Lilly were published in a supplement issue of one diabetes technology journal and most of these will be presented. A number of other publications (also one in a high ranked journal) about their inhaled insulin were from another company: MannKind. The driving force behind Technosphere insulin (TI) - which is the only one still in clinical development - is Al Mann; he has put a lot of his personal fortune in this development. We will know the opinion of the regulatory authorities about TI in the near future; however, I am personally relatively confident that the Food and Drug Administration will provide TI with market approval. The more critical question for me is: will diabetologists and patients jump on this product once it becomes commercially available? Will it become a commercial success? In view of many negative feelings in the scientific community about inhaled insulin, it might be of help that MannKind publish their studies with TI systematically. Acknowledging being a believer in this route of insulin administration myself, one has to state that Exubera and AIR insulin had not offered profound advantages in terms of pharmacokinetic (PK) and pharmacodynamic (PD) properties in comparison with subcutaneously (SC) applied regular human insulin (RHI) and rapid-acting insulin analogues. The time-action profiles of these inhaled insulins were more or less comparable with that of rapid-acting insulin analogues. This is clearly different with TI which exhibits a strong metabolic effect shortly after application and a rapid decline in the metabolic effect thereafter; probably the duration of action is
Lomax Michael A
Full Text Available Abstract Background The ubiquitin-proteasome system is the predominant pathway for myofibrillar proteolysis but a previous study in C2C12 myotubes only observed alterations in lysosome-dependent proteolysis in response to complete starvation of amino acids or leucine from the media. Here, we determined the interaction between insulin and amino acids in the regulation of myotube proteolysis Results Incubation of C2C12 myotubes with 0.2 × physiological amino acids concentration (0.2 × PC AA, relative to 1.0 × PC AA, significantly increased total proteolysis and the expression of 14-kDa E2 ubiquitin conjugating enzyme (p Conclusion In a C2C12 myotube model of myofibrillar protein turnover, amino acid limitation increases proteolysis in a ubiquitin-proteasome-dependent manner. Increasing amino acids or leucine alone, act additively with insulin to down regulate proteolysis and expression of components of ubiquitin-proteasome pathway. The effects of amino acids on proteolysis but not insulin and leucine, are blocked by inhibition of the mTOR signalling pathway.
Romualdi, Daniela; De Cicco, Simona; Gagliano, Donatella; Busacca, Matteo; Campagna, Giuseppe; Lanzone, Antonio; Guido, Maurizio
Metformin has been reported to reduce the risk of gestational diabetes (GD) in women with polycystic ovarian syndrome (PCOS). However, little is known about the mechanisms of action of this drug during pregnancy. In the attempt to fill this gap, we performed a prospective longitudinal study providing a detailed examination of glucose and insulin metabolism in pregnant women with PCOS undergoing metformin therapy. We enrolled 60 women with PCOS who conceived while undergoing metformin treatment. An oral glucose tolerance test and a euglycemic-hyperinsulinemic clamp were performed at each trimester of gestation in 47 ongoing pregnancies. Twenty-two of the study subjects had development of GD despite the treatment. At baseline, insulin sensitivity was comparable between women who had development of GD and women who did not. A progressive decline in this parameter occurred in all subjects, independently of the trimester of GD diagnosis. Insulin secretion was significantly higher during the first trimester in patients with an early failure of metformin treatment. Women with third trimester GD and women with no GD exhibited a significant increase in insulin output as gestation proceeded. All newborns were healthy and only one case of macrosomia was observed. Women with PCOS who enter pregnancy in a condition of severe hyperinsulinemia have development of GD earlier, independently of metformin treatment. The physiologic deterioration of insulin sensitivity is not affected by the drug and does not predict the timing and severity of the glycemic imbalance. Despite the high incidence of GD observed, the drug itself or the intensive monitoring probably accounted for the good neonatal outcome.
Rosenfalck, A M; Thorsby, P; Kjems, L
beta-cell function. In a double-blind, double dummy crossover design, patients attended three study days where the following insulin injections in combination with placebo were given in a random order: IAsp (0.15 IU/kg body weight) immediately before the meal, or insulin Actrapid (0.15 IU......The effect on postprandial blood glucose control of an immediately pre-meal injection of the rapid acting insulin analogue Aspart (IAsp) was compared with that of human insulin Actrapid injected immediately or 30 minutes before a test meal in insulin-treated type 2 diabetic patients with residual....../kg) immediately (Act0) or 30 minutes before (Act-30) a test meal. We studied 25 insulin-requiring type 2 diabetic patients, including 14 males and 11 females, with a mean age of 59.7 years (range, 43-71), body mass index 28.3 kg/m2 (range, 21.9-35.0), HbA1c 8.5% (range, 6.8-10.0), glucagon-stimulated C-peptide 1...
Full Text Available Abstract Whilst some populations have recently experienced dramatic declines in malaria, the majority of those most at risk of Plasmodium falciparum malaria still lack access to effective treatment with artemisinin combination therapy (ACT and others are already facing parasites resistant to artemisinins. In this context, there is a crucial need to improve both access to and targeting of ACT through greater availability of good quality ACT and parasitological diagnosis. This is an issue of increasing urgency notably in the private commercial sector, which, in many countries, plays an important role in the provision of malaria treatment. The Affordable Medicines Facility for malaria (AMFm is a recent initiative that aims to increase the provision of affordable ACT in public, private and NGO sectors through a manufacturer-level subsidy. However, to date, there is little documented experience in the programmatic implementation of subsidized ACT in the private sector. Cambodia is in the unique position of having more than 10 years of experience not only in implementing subsidized ACT, but also rapid diagnostic tests (RDT as part of a nationwide social marketing programme. The programme includes behaviour change communication and the training of private providers as well as the sale and distribution of Malarine, the recommended ACT, and Malacheck, the RDT. This paper describes and evaluates this experience by drawing on the results of household and provider surveys conducted since the start of the programme. The available evidence suggests that providers' and consumers' awareness of Malarine increased rapidly, but that of Malacheck much less so. In addition, improvements in ACT and RDT availability and uptake were relatively slow, particularly in more remote areas. The lack of standardization in the survey methods and the gaps in the data highlight the importance of establishing a clear system for monitoring and evaluation for similar initiatives
Michael A Weiss
Full Text Available The engineering of insulin analogues illustrates the application of structure-based protein design to clinical medicine. Such design has traditionally been based on structures of wild-type insulin hexamers in an effort to optimize the pharmacokinetic (PK and pharmacodynamic properties of the hormone. Rapid-acting insulin analogues (in chronological order of their clinical introduction, Humalog ® [Eli Lilly & Co.], Novolog ® [Novo-Nordisk], and Apidra ® [Sanofi-Aventis] exploit the targeted destabilization of subunit interfaces to facilitate capillary absorption. Conversely, long-acting insulin analogues exploit the stability of the insulin hexamer and its higher-order self-assembly within the subcutaneous depot to enhance basal glycemic control. Current products either operate through isoelectric precipitation (insulin glargine, the active component of Lantus ® ; Sanofi-Aventis or employ an albumin-binding acyl tether (insulin detemir, the active component of Levemir ® ; Novo-Nordisk. Such molecular engineering has often encountered a trade-off between PK goals and product stability. Given the global dimensions of the diabetes pandemic and complexity of an associated cold chain of insulin distribution, we envisage that concurrent engineering of ultra-stable protein analogue formulations would benefit the developing world, especially for patients exposed to high temperatures with inconsistent access to refrigeration. We review the principal mechanisms of insulin degradation above room temperature and novel molecular approaches toward the design of ultra-stable rapid-acting and basal formulations.
... the Spikes Is mealtime insulin right for you? Insulin Secretagogues September 2017 Download PDFs English Espanol Editors ... Additional Resources Affordable Insulin Project FDA What are insulin secretagogues? Insulin secretagogues are one type of medicine ...
Can Fasting Glucose Levels or Post-Breakfast Glucose Fluctuations Predict the Occurrence of Nocturnal Asymptomatic Hypoglycemia in Type 1 Diabetic Patients Receiving Basal-Bolus Insulin Therapy with Long-Acting Insulin?
Mitsuishi, Sumie; Nishimura, Rimei; Ando, Kiyotaka; Tsujino, Daisuke; Utsunomiya, Kazunori
To investigate whether the occurrence of nocturnal asymptomatic hypoglycemia may be predicted based on fasting glucose levels and post-breakfast glucose fluctuations. The study subjects comprised type 1 diabetic patients who underwent CGM assessments and received basal-bolus insulin therapy with long-acting insulin. The subjects were evaluated for I) fasting glucose levels and II) the range of post-breakfast glucose elevation (from fasting glucose levels to postprandial 1- and 2-hour glucose levels). The patients were divided into those with asymptomatic hypoglycemia during nighttime and those without for comparison. Optimal cut-off values were also determined for relevant parameters that could predict nighttime hypoglycemia by using ROC analysis. 64 patients (mean HbA1c 8.7 ± 1.8%) were available for analysis. Nocturnal asymptomatic hypoglycemia occurred in 23 patients (35.9%). Fasting glucose levels (I) were significantly lower in those with hypoglycemia than those without (118 ± 35 mg/dL vs. 179 ± 65 mg/dL; P fasting glucose level 54 mg/dL (0.65/0.61/0.71, P = 0.006), 2-h postprandial elevation > 78 mg/dL (0.65/0.73/0.71, P = 0.005). Nocturnal asymptomatic hypoglycemia was associated with increases in post-breakfast glucose levels in type 1 diabetes. Study findings also suggest that fasting glucose levels and the range of post-breakfast glucose elevation could help predict the occurrence of nocturnal asymptomatic hypoglycemia.
Mathiesen, Elisabeth R
in insulin requirements during pregnancy necessitate short-acting insulins for postprandial control of hyperglycemia. The fast-acting insulin analogue insulin aspart has been tested in a large, randomized trial of pregnant women with Type 1 diabetes and offers benefits in control of postprandial......Pregnancy in women with diabetes is associated with an increased risk of obstetric complications and perinatal mortality. Maintenance of near-normal glycemia during pregnancy can bring the prevalence of fetal, neonatal and maternal complications closer to that of the nondiabetic population. Changes...... and no increase in insulin antibodies was found. Thus, the use of insulin aspart in pregnancy is regarded safe....
Soriano-Heras, Enrique; Blaya-Haro, Fernando; Molino, Carlos; de Agustín Del Burgo, José María
The purpose of this article is to develop a new concept of modular and operative prosthetic hand based on rapid prototyping and a novel shape-memory-alloy (SMA) actuator, thus minimizing the manufacturing costs. An underactuated mechanism was needed for the design of the prosthesis to use only one input source. Taking into account the state of the art, an underactuated mechanism prosthetic hand was chosen so as to implement the modifications required for including the external SMA actuator. A modular design of a new prosthesis was developed which incorporated a novel SMA actuator for the index finger movement. The primary objective of the prosthesis is achieved, obtaining a modular and functional low-cost prosthesis based on additive manufacturing executed by a novel SMA actuator. The external SMA actuator provides a modular system which allows implementing it in different systems. This paper combines rapid prototyping and a novel SMA actuator to develop a new concept of modular and operative low-cost prosthetic hand.
Mattocks, Kristin M; Mengeling, Michelle; Sadler, Anne; Baldor, Rebecca; Bastian, Lori
Congress enacted the Veterans Access, Choice, and Accountability Act of 2014 [Veterans Choice Act (VCA)] to improve access to timely, high-quality health care for Veterans. Although Congress mandated that VCA must begin within 90 days of passage of the legislation, no guidelines were provided in the legislation to ensure that Veterans had access to an adequate number of community providers across different specialties of care or distinct geographic areas, including rural areas of the country. To examine VCA policy implementation across a sampling of Veterans Health Administration (VHA) Medical Centers. We conducted a qualitative study of 43 VHA staff and providers by conducting in-person interviews at 5 VA medical centers in the West, South, and Midwest United States. Interview questions focused on perceptions and experiences with VCA and challenges related to implementation for VHA staff and providers. We identified 3 major themes to guide description of choice implementation: (1) VCA implemented too rapidly with inadequate preparation; (2) community provider networks insufficiently developed; and (3) communication and scheduling problems with subcontractors may lead to further delays in care. Our evaluation suggests that VCA was implemented far too rapidly, with little consideration given to the adequacy of community provider networks available to provide care to Veterans. Given the challenges we have highlighted in VCA implementation, it is imperative that the VHA continue to develop care coordination systems that will allow the Veterans to receive seamless care in the community.
Alicino, Ilaria; Giglio, Mariateresa; Manca, Fabio; Bruno, Francesco; Puntillo, Filomena
Ziconotide is a nonopioid intrathecal analgesic drug used to manage moderate to severe chronic pain. The aim of this work is to assess the safety and efficacy of intrathecal (IT) combination of ziconotide and morphine in malignant pain refractory to high doses of oral opioids. Patients with malignant pain refractory to high oral opioids doses with a mean visual analogue scale of pain intensity (VASPI) score of ≥ 70 mm were enrolled. An IT combination therapy was administered: Ziconotide was started at a dose of 2.4 μg/day, followed by increases of 1.2 μg/day at intervals of at least 7 days, and an initial IT daily dose of morphine was calculated based on its oral daily dose. Percentage change in VASPI scores from baseline was calculated at 2 days, at 7 days, and weekly until the first 28 days. The mean percentage change of VASPI score from baseline was used for efficacy assessment. Safety was monitored based on adverse events and routine laboratory values. Twenty patients were enrolled, with a mean daily VASPI score at rest of 90±7. All had a disseminated cancer with bone metastases involving the spine. The percentage changes in VASPI mean scores from baseline to 2 days, 7 days, and 28 days were 39±13% (95% confidence interval [CI]=13.61-64.49, Pziconotide and morphine allows safe and rapid control of oral opioid-refractory malignant pain. Copyright © 2011 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.
Caldwell, Brent O; Adamson, Simon J; Crane, Julian
Improved smoking cessation rates are urgently required if New Zealand is to reach its target of a smokefree nation by 2025, during which some 600,000 smokers will need to quit. Nicotine replacement therapy remains a core part of the pharmacological approach to smoking cessation. Oral nicotine solutions with rapid onset have recently become available. We have examined the effect of a nicotine spray and a nicotine patch on smoking cessation for 12 months. We enrolled potential participants-smokers wanting to quit aged 18-70 years, who smoked ≥9 cigarettes per day-with Fagerström Test of Nicotine Dependence score ≥3 in a double-blind trial in 3 trial sites. Smokers were randomized to a nicotine or placebo spray for 6 months, and all received nicotine patches daily for 5 months. They were followed at regular intervals for 12 months. A total of 1,423 subjects were randomized to nicotine oral spray (1mg of nicotine free base per spray) plus nicotine patch or a placebo spray and nicotine patch. The nicotine mouth spray plus nicotine patch showed significant improvements in prolonged abstinence for all measures to 6 months (7 consecutive days at each visit for 6 months: 15.5% vs. 10.6%; p = .006) for the combination versus placebo and nicotine patch. Thereafter, the differences were not significant. The addition of a nicotine mouth spray to a nicotine replacement patch in a population of smokers receiving a low level of behavioral support improved early quitting, but the effects were not sustained. © The Author 2014. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco. All rights reserved. For permissions, please e-mail: email@example.com.
Scheen, André J; Paquot, Nicolas
In a patient with type 2 diabetes not well controlled with a basal insulin - metformin combination, several therapeutic options may be considered: intensifying insulin therapy with different schemes (appropriate titration using a more favourable basal insulin analogue, adding one, two or three rapid-acting insulin analogues, shift to two or three premix insulin injections), adding a dipeptidyl peptidase-4 inhibitor (gliptin) or an inhibitor of sodium-glucose cotransporters type 2 (gliflozin), or combining a glucagon-like peptide-1 receptor agonist with basal insulin. The choice should be made according the individual profile and preference of the patient, in a personalized approach, taking into account the advantages and disadvantages of each therapeutic solution.
Physical work effects a transitory enhanced affinity of insulin to its receptor in the stressed muscles and thereby a better efficiency. Therefore, in sports lasting for 30 min and more the basal and/or bolus doses of insulin have to be reduced in order to prevent hypoglycemia. An alternative supply of additional carbohydrates prior to physical work is often not practicable. Injections of insulin into areas of the body not involved in muscular work do not give sufficient warranty against hypoglycemic reactions. A new short-acting insulin-analogue (Lispro) shows a reduced effect on blood glucose levels after 3 h as compared to regular insulin. Therefore, it could be of advantage for insulin dependent diabetics doing their exercise at this time.
Full Text Available Hideaki Katagiri,1 Masanori Taketsuna,2 Shinpei Kondo,3 Kenta Kajimoto,4 Etsuko Aoi,5 Yuka Tanji1 1Bio Medicine, 2Statistical Sciences, 3Post Marketing Study Management, 4Scientific Communications, Medicines Development Unit Japan, 5Global Patient Safety Japan, Quality and Patient Safety, Eli Lilly Japan K.K., Kobe, Japan Objective: The objective of this study was to evaluate the safety and effectiveness of rapid-acting intramuscular (IM olanzapine in the treatment of acute agitation associated with schizophrenia in real-world clinical settings in Japan.Methods: In this multicenter, postmarketing surveillance (PMS study, patients with acute agitation associated with schizophrenia were treated with IM olanzapine daily in a daily clinical setting. The observational period ranged from 1 to 7 days, including the day of initial administration. Safety was assessed by reporting treatment-emergent adverse events (TEAEs and adverse drug reactions (ADRs. The Positive and Negative Syndrome Scale – Excited Component (PANSS-EC score was used to evaluate effectiveness at baseline and at 2 hours (after each administration, 2 days, and 3 days (end of the observational period from the last administration of the IM olanzapine injection.Results: The safety analysis set included 999 patients, and the initial dose of 10 mg was administered to 955 patients. TEAEs were reported in 28 patients (36 events, the most common of which were dyslalia (5 patients, akathisia and somnolence (4 patients each, hepatic function abnormal (3 patients, and constipation and dehydration (2 patients each. One serious adverse event of akathisia occurred during the observation period. The PANSS-EC score (mean ± standard deviation was 23.3±6.4 (n=625 at baseline, 16.9±7.0 (n=522 at 2 hours after initial injection, and 14.9±6.5 (n=650 at the last observation carried forward.Conclusion: The results of this Japanese PMS study demonstrated that IM olanzapine is safe and has a
T I Romantsova
Full Text Available Aims. To study the dynamics of body weight, waist circumference, blood lipid and insulin demand in patients with type 2 diabetes mellitus (T2DM during first year of combined treatment with metformin and insulin analogues, compared with insulin analogue monotherapy.Materials and Methods. We examined 78 patients with T2DM on newly initiated insulin therapy, including 54 females and 24 males. Median age was 56 [51.0; 64.0] years, median disease duration – 9 [6.8;14.0] years. Participants were subdivided in two groups. First group was comprised of 48 subjects (33 females and 15 males, who received monotherapy with insulin analogues (glargine, de- temir, biphasic Aspart 30 and Humalog Mix 25 or rapid-acting lispro and aspart. Second group included 30 patients (18 females and12 males, who were treated with combined therapy (insulin analogues plus metformin. We measured HbA1c, plasma lipid composition, BMI, waist circumference and insulin demand initially and after one year of follow-up.Results. We showed that combined therapy vs. insulin monotherapy allows better glycemic compensation while reducing insulin demand and lowering risks for weight gain.Conclusions. Combined insulin analogue plus metformin treatment delivers better metabolic control in patients with T2DM and is as- sociated with lower risks for body weight gain and increase in insulin demand against monotherapy with insulin analogues.
Manuel E. Licea Puig
diabetes mellitus (DM. The recombinant technology of deoxyribonucleic acid (DNA has allowed the development of human insulin; however, this has not totally solved the problems related to immunogenecity, among other problems. Therefore, the new technologies are applied to create insulin analogues. It is our purpose to review relevant pharmacological and clinical aspects related to the insulin analogues, as well as their usefulness in the treatment of DM. The insulin analogues result from biochemical modifications of human insulin. These modifications of the insulin molecule alter not only the absorption, but also the beginning and duration of the action, which offer advantages over the conventional insulins. At present, there are three rapid acting insulin analogues: insulin lispro, insulin aspart and glulisine; and three long acting analogues; glargine, detemir and albulin. Albulin is the latest long acting analogue reported. At present, it is being subjected to various in vitro and in vivo studies. Besides, there have been developed diverse formulations where the rapid acting insulin analogues are premixed with the long acting analogues. The rapid acting insulin analogues have showed a modest global benefit against the conventional insulins in type 1 diabetics. The long acting analogues focus their attention in those persons with DM with nocturnal hypoglycemic episodes. Longer term studies are necessary to confirm the safety and benefits of these preparations, as well as to determine their effect on the micro- and macroangiopathic complications of DM.
... Your Health Resources Drugs, Procedures & Devices Prescription Medicines Insulin Therapy Insulin Therapy Share Print When you digest food, your ... you eat into glucose (a form of sugar). Insulin allows this glucose to enter all the cells ...
Woo, Vincent C
The major abnormality in both type 1 and type 2 diabetes is insulin deficiency. The methods of replacing insulin have improved throughout the decades, but hypoglycemia is still the limiting factor for many individuals with diabetes, and it prevents them from achieving ideal glycemic targets. New insulin and newer delivery systems are being developed that can improve some of the limitations of current insulins or make the delivery of insulins more acceptable for some patients. Extending the duration of action of basal insulins and shortening the peak of fast-acting insulins may have advantages for individuals with diabetes. Different delivery systems may make insulin more acceptable to patients and may have other advantages, which may aid in attaining better glycemic control. Copyright © 2015 Canadian Diabetes Association. Published by Elsevier Inc. All rights reserved.
Frödin, M; Gammeltoft, S
We have investigated the effects of insulin-like growth factors (IGFs), basic fibroblast growth factor (bFGF), and nerve growth factor (NGF) on DNA synthesis in cultured chromaffin cells from fetal, neonatal, and adult rats by using 5-bromo-2'-deoxyuridine (BrdUrd) pulse labeling for 24 or 48 h...... and immunocytochemical staining of cell nuclei. After 6 days in culture in the absence of growth factors, nuclear BrdUrd incorporation was detected in 30% of fetal chromaffin cells, 1.5% of neonatal cells, and 0.1% of adult cells. Addition of 10 nM IGF-I or IGF-II increased the fraction of BrdUrd-labeled nuclei to 50...... and 10- to 20-fold in adult chromaffin cells compared with the effect of each growth factor alone. In contrast, the action of bFGF and NGF added together in the absence of IGFs was not synergistic or additive. IGF-II acted also as a survival factor on neonatal chromaffin cells and the cell survival...
Worldwide, many people with type 2 diabetes are not at recommended glycemic targets and remain at increased risk of microvascular and macrovascular complications. Reaching recommended glycemic targets requires normalizing both fasting and postprandial glucose (PPG). For some patients, this will require addition of a prandial insulin delivered by injection to control PPG excursions. Evidence from epidemiological studies suggests an association between postprandial hyperglycemia and cardiovascular disease, and thus, expert guidelines recommend that treatment for elevated PPG not be delayed. Indeed, studies have demonstrated that PPG makes the greatest contribution to HbA1c in patients who are approaching, but have not yet reached HbA1c insulin is critical in suppressing hepatic glucose output (and therefore PPG levels) after a meal. Rapid-acting insulin analogs, with their faster onset and shorter duration of action, offer advantages over regular human insulin. Unfortunately, even with improved pharmacokinetic/pharmacodynamic characteristics, rapid-acting insulin analogs are still unable to fully reproduce the rapid release of insulin into the portal circulation and suppression of hepatic glucose output that occurs in the individual without diabetes after starting a meal. The next generation of rapid-acting insulin analogs will have an even more favorable pharmacokinetic profile that should allow patients to further improve glycemic control. Continuous subcutaneous insulin infusion (CSII) represents another option for intensifying therapy and improving postprandial control in some patients, and studies have shown that the benefits are sustainable long-term. However, it is currently unclear which patients stand to benefit the most from the extra expense and complexity of a CSII regimen, and further studies are needed.
Gorevic Peter D
Full Text Available Abstract Background Putatively active drugs are often intraventricularly administered to gain direct access to brain and circumvent the blood-brain barrier. A few studies on the normal central nervous system (CNS have shown, however, that the distribution of materials after intraventricular injections is much more limited than presumed and their exit from cerebrospinal fluid (CSF is more rapid than generally believed. In this study, we report the intracranial distribution and the clearance from CSF and adjacent CNS tissue of radiolabeled insulin-like growth factor-1 after injection into one lateral ventricle of the normal rat brain. Methods Under barbiturate anesthesia, 125I-labeled insulin-like growth factor-1 (IGF-1 was injected into one lateral ventricle of normal Sprague-Dawley rats. The subsequent distribution of IGF-1 through the cerebrospinal fluid (CSF system and into brain, cerebral blood vessels, and systemic blood was measured over time by gamma counting and quantitative autoradiography (QAR. Results Within 5 min of infusion, IGF-1 had spread from the infused lateral ventricle into and through the third and fourth ventricles. At this time, 25% of the infused IGF-1 had disappeared from the CSF-brain-meningeal system; the half time of this loss was 12 min. The plasma concentration of cleared IGF-1 was, however, very low from 2 to 9 min and only began to rise markedly after 20 min. This delay between loss and gain plus the lack of radiotracer in the cortical subarachnoid space suggested that much of the IGF-1 was cleared into blood via the cranial and/or spinal nerve roots and their associated lymphatic systems rather than periventricular tissue and arachnoid villi. Less than 10% of the injected radioactivity remained in the CSF-brain system after 180 min. The CSF and arteries and arterioles within the subarachnoid cisterns were labeled with IGF-1 within 10 min. Between 60 and 180 min, most of the radioactivity within the cranium was
Design and rationale of a large, international, prospective cohort study to evaluate the occurrence of malformations and perinatal/neonatal death using insulin detemir in pregnant women with diabetes in comparison with other long-acting insulins
Mathiesen, Elisabeth R; Andersen, Henning; Sofia I I Kring; Damm, Peter
Background There are a lack of data regarding the effect of basal insulin analogues on rates of events like congenital malformation and perinatal mortality in diabetic pregnancy. Methods The present study is a prospective, non-interventional, multicentre cohort study conducted in seven countries, designed to assess the safety of insulin detemir during pregnancy, and to monitor the health status of resulting infants (exposed in utero) up to 1?year of age. The study population includes women wi...
Design and rationale of a large, international, prospective cohort study to evaluate the occurrence of malformations and perinatal/neonatal death using insulin detemir in pregnant women with diabetes in comparison with other long-acting insulins.
Mathiesen, Elisabeth R; Andersen, Henning; Kring, Sofia I I; Damm, Peter
There are a lack of data regarding the effect of basal insulin analogues on rates of events like congenital malformation and perinatal mortality in diabetic pregnancy. The present study is a prospective, non-interventional, multicentre cohort study conducted in seven countries, designed to assess the safety of insulin detemir during pregnancy, and to monitor the health status of resulting infants (exposed in utero) up to 1 year of age. The study population includes women with type 1 or type 2 diabetes, who are pregnant and being treated with insulin. Data will be collected in the context of routine practice. The primary endpoint is the proportion of pregnancies in women treated with insulin detemir, compared with other basal insulin regimens, which do not result in any of the following events: major congenital malformations, perinatal death or neonatal death. A sample size of 3075 pregnancies was calculated to provide an 80% power to detect a difference of 3.5% between groups in the primary endpoint at a 5% level. The study will also examine other important maternal endpoints (e.g., incidences of severe hypoglycaemia and pre-eclampsia) and perinatal outcomes such as overweight neonates, as well as infant outcomes at 1 year of age. It has a fixed recruitment period from 2013 to 2018, enrolling all eligible patients, and is expected to inform future prescribing with basal insulins in diabetic pregnancy. ClinicalTrials.gov: NCT01892319 (date registered: 27.06.2013).
Walz, Helena A; Härndahl, Linda; Wierup, Nils
Inadequate islet adaptation to insulin resistance leads to glucose intolerance and type 2 diabetes. Here we investigate whether beta-cell cAMP is crucial for islet adaptation and prevention of glucose intolerance in mice. Mice with a beta-cell-specific, 2-fold overexpression of the c...... did not reveal reduced insulin sensitivity in these tissues. Significant steatosis was noted in livers from high-fat-fed wild-type and RIP-PDE3B/2 mice and liver triacyl-glycerol content was 3-fold higher than in wild-type mice fed a control diet. Histochemical analysis revealed severe islet...... perturbations, such as centrally located alpha-cells and reduced immunostaining for insulin and GLUT2 in islets from RIP-PDE3B/2 mice. Additionally, in vitro experiments revealed that the insulin secretory response to glucagon-like peptide-1 stimulation was markedly reduced in islets from high-fat-fed RIP-PDE3B...
Singh, Suchita; Prakash, Y S; Linneberg, Allan
Obesity, metabolic syndrome, and asthma are all rapidly increasing globally. Substantial emerging evidence suggests that these three conditions are epidemiologically and mechanistically linked. Since the link between obesity and asthma appears to extend beyond mechanical pulmonary disadvantage...... and highlights the molecular consequences of insulin-related metabolic signaling cascades that could adversely affect lung structure and function. Examples include airway smooth muscle proliferation and contractility and regulatory signaling networks that are associated with asthma. These aspects of insulin...
Cornford, Andrea S; Hinko, Alexander; Nelson, Rachael K; Barkan, Ariel L; Horowitz, Jeffrey F
Prolonged overeating and the resultant weight gain are clearly linked with the development of insulin resistance and other cardiometabolic abnormalities, but adaptations that occur after relatively short periods of overeating are not completely understood. The purpose of this study was to characterize metabolic adaptations that may accompany the development of insulin resistance after 2 weeks of overeating. Healthy, nonobese subjects (n = 9) were admitted to the hospital for 2 weeks, during which time they ate ∼4000 kcals·day(-1) (70 kcal·kg(-1) fat free mass·day(-1)). Insulin sensitivity was estimated during a meal tolerance test, and a muscle biopsy was obtained to assess muscle lipid accumulation and protein markers associated with insulin resistance, inflammation, and the regulation of lipid metabolism. Whole-body insulin sensitivity declined markedly after 2 weeks of overeating (Matsuda composite index: 8.3 ± 1.3 vs. 4.6 ± 0.7, p insulin resistance and inflammation (i.e., phosphorylation of IRS-1-Ser(312), Akt-Ser(473), and c-Jun N-terminal kinase) were not altered by overeating. Intramyocellular lipids tended to increase after 2 weeks of overeating (triacylglyceride: 7.6 ± 1.6 vs. 10.0 ± 1.8 nmol·mg(-1) wet weight; diacylglyceride: 104 ± 10 vs. 142 ± 23 pmol·mg(-1) wet weight) but these changes did not reach statistical significance. Overeating induced a 2-fold increase in 24-h insulin response (area under the curve (AUC); p increase in muscle lipid accumulation. In summary, our findings suggest alterations in skeletal muscle metabolism may not contribute meaningfully to the marked whole-body insulin resistance observed after 2 weeks of overeating.
Bowe, James E; Foot, Victoria L; Amiel, Stephanie A; Huang, Gao Cai; Lamb, Morgan W; Lakey, Jonathan; Jones, Peter M; Persaud, Shanta J
This study was designed to determine the effects of 10 and 13 amino acid forms of kisspeptin on dynamic insulin secretion from mammalian islets since it is not clear from published data whether the shorter peptide is stimulatory while the longer peptide inhibits insulin release. Insulin secretion was measured by radioimmunoassay following perifusion of human, pig, rat and mouse isolated islets with kisspeptin-10 or kisspeptin-13 in the presence of 20 mM glucose. Both peptides stimulated rapid, reversible potentiation of glucose-stimulated insulin secretion from islets of all species tested. These data indicate that both kisspeptin-10 and kisspeptin-13, which is an extension of kisspeptin-10 by three amino acids, act directly at islet β-cells of various species to potentiate insulin secretion, and suggest that inhibitory effects reported in earlier studies may reflect differences in experimental protocols.
Cengiz, Eda; Weinzimer, Stuart A; Sherr, Jennifer L; Tichy, Eileen M; Carria, Lori; Cappiello, Darryll; Steffen, Amy; Tamborlane, William V
This study was undertaken to investigate the effect of an insulin infusion site warming device, the InsuPatch(40)(™) (IP(40)) (InsuLine Medical Ltd., Petach-Tikvah, Israel), on insulin aspart pharmacodynamics (PD) and pharmacokinetics (PK) in adolescents with type 1 diabetes. Seventeen subjects with type 1 diabetes (age, 15±1 years; hemoglobin A1c, 7.5±0.2% [58±2.2 mmol/mol]) underwent two euglycemic clamps performed on separate mornings with and without IP(40) activation with warming temperature at 40°C. On both days, the basal infusion was suspended, and glucose levels were maintained between 90 and 100 mg/dL by a variable rate dextrose infusion for up to 5 h after a 0.2 U/kg bolus of insulin aspart. Time to peak insulin action and time to half-maximal action occurred earlier with a greater early glucodynamic effect (area under the curve [AUC] for glucose infusion rate from 0 to 30 min) with IP(40) than without the IP(40), whereas the AUC for the time-action profile and the peak action did not differ with and without infusion site warming. PK parameters were in agreement with PD parameters, namely, a significantly earlier time to reach the maximum increment in insulin concentrations and greater early bioavailability (AUC for the change in insulin concentration from 0 to 30 min) with the IP(40). The tail of the plasma insulin response curve was also shortened with infusion site warming, with the time to reach baseline insulin concentration occurring significantly earlier (P=0.04). Our data demonstrate that skin warming around the infusion site to 40°C with the IP(40) is an effective means to accelerate absorption and action of rapid-acting insulin. These improvements in time-action responses have the potential to enhance the performance of open- and closed-loop insulin delivery systems.
Design and rationale of a large, international, prospective cohort study to evaluate the occurrence of malformations and perinatal/neonatal death using insulin detemir in pregnant women with diabetes in comparison with other long-acting insulins
Mathiesen, Elisabeth R.; Andersen, Henning; Kring, Sofia I.I.
in the context of routine practice. The primary endpoint is the proportion of pregnancies in women treated with insulin detemir, compared with other basal insulin regimens, which do not result in any of the following events: major congenital malformations, perinatal death or neonatal death. A sample size of 3075......Background: There are a lack of data regarding the effect of basal insulin analogues on rates of events like congenital malformation and perinatal mortality in diabetic pregnancy. Methods: The present study is a prospective, non-interventional, multicentre cohort study conducted in seven countries...... pregnancies was calculated to provide an 80% power to detect a difference of 3.5% between groups in the primary endpoint at a 5% level. Discussion: The study will also examine other important maternal endpoints (e.g., incidences of severe hypoglycaemia and pre-eclampsia) and perinatal outcomes...
Design and rationale of a large, international, prospective cohort study to evaluate the occurrence of malformations and perinatal/neonatal death using insulin detemir in pregnant women with diabetes in comparison with other long-acting insulins
Mathiesen, Elisabeth R; Andersen, Henning; Kring, Sofia I I
in the context of routine practice. The primary endpoint is the proportion of pregnancies in women treated with insulin detemir, compared with other basal insulin regimens, which do not result in any of the following events: major congenital malformations, perinatal death or neonatal death. A sample size of 3075......BACKGROUND: There are a lack of data regarding the effect of basal insulin analogues on rates of events like congenital malformation and perinatal mortality in diabetic pregnancy. METHODS: The present study is a prospective, non-interventional, multicentre cohort study conducted in seven countries...... pregnancies was calculated to provide an 80% power to detect a difference of 3.5% between groups in the primary endpoint at a 5% level. DISCUSSION: The study will also examine other important maternal endpoints (e.g., incidences of severe hypoglycaemia and pre-eclampsia) and perinatal outcomes...
Full Text Available The paper discusses the results of studies on physical and chemical properties of kvasi-living self-organizing insulin-based system, and on the effectiveness of its oral administration. The purpose of the studies was to modify positively charged amino acid residues into negatively charged residues of dicarboxylic acids. The process of bioorganic combinatorial synthesis produced more than 100 thousand fragments capable of self-organization in the insulin receptor. Self-organization is due to the fact that peptides were previously a part of the whole – namely, insulin molecule. These peptides had small size, and could be easily absorbed by intestines. They also had a long duration of circulation in blood and reacted with insulin receptor in a fashion similar to injected insulin. It is shown that a single oral application of such system leads to statistically significant and sustained reduction in blood glucose levels within 24 hours of application. The effect is observed in both cases: while taking the drug on an empty stomach, and with glucose and food load up to 7.11 mmol / L. A single dose of the drug led to a plateau of stable glucose levels and prevented hypoglycemia and glucose level jumps when applied to rats (control group. The kvasi-living system was obtained by partial proteolysis of recombinant insulin with pepsin, followed by partial modification of peptides with succinic anhydride
Raz, Itamar; Bitton, Gabriel; Feldman, Dmitry; Alon, Tal; Pfutzner, Andreas; Tamborlane, William V.
Background: Delays in the time-action profiles of premeal boluses of rapid-acting insulin analogs contribute to early postmeal hyperglycemia in patients with diabetes. We tested whether applying local heat to skin around the injection site to increase the rate of insulin absorption reduces postprandial hyperglycemia in patients with type 2 diabetes. Methods: Fourteen patients with type 2 diabetes (4 females; age 61.6 ± 8.4 years, HbA1c 8.42 ± 1.13%; BMI 29.10 ± 5.61 kg/m2) on intensified insulin therapy underwent 5-hour meal tolerance tests (MTTs) with a standardized liquid meal after an overnight fast on 2 study days. Subjects injected 0.2 U/kg of insulin aspart or lispro subcutaneously into the abdominal skin on both days with and without the use of the InsuPad device. Results: Following the premeal bolus injection of rapid-acting insulin analog, infusion site warming led to a rise in plasma insulin levels to peak concentrations that were significantly earlier than without skin warming (mean ± SD 52 ± 26.7 vs 80 ± 51.3 minutes, P insulin levels during the first hour after injection (mean ± SD 63.5 ± 32.7 IU vs 48.0 ± 25.0 uU.min/ml, P = .019). As a result, the area under the curve of the postprandial glucose excursion during the first 2 hours (the primary study outcome) and the entire 5 hours after the meal were significantly reduced (P = .007 and P = .03, respectively) with skin warming around the injection site. Discussion and Conclusions: Use of the InsuPad to increase the rate of insulin absorption provides an effective means to achieve better control of postmeal glucose excursions in type 2 diabetic patients receiving premeal injections of rapid-acting insulin analogs. PMID:25883166
Cherubini, V; Pintaudi, B; Iannilli, A; Pambianchi, M; Ferrito, L; Nicolucci, A
Growth hormone (GH) secretion is increased in pre-pubertal children with type 1 diabetes and GH excess produces insulin resistance. Early-morning insulinopenia contributes to lower insulin-like growth factor (IGF-I) levels and to GH hypersecretion. To evaluate differences in GH/IGF-I axis of pre-pubertal children with type 1 diabetes treated with glargine or detemir as long-acting insulin analogues, which was the main outcome measure, and to compare insulin effects in obtaining good metabolic control. Children with type 1 diabetes. This was a 32-week, randomized, open-label, two-period, cross-over comparison between bedtime glargine and twice-daily detemir insulin, involving pre-pubertal children in care at a diabetes pediatric centre. After a 8-week-run-in period subjects were randomized to bedtime glargine or twice-daily detemir insulin administration. After a 12-week period treatments were inverted and continued for additional 12 weeks. Overall, 15 pre-pubertal children (53.3% males, mean age 8.6±1.5 years, duration of diabetes 4.2±1.5 years) completed the study. Groups did not differ for GH/IGF axis and HbA1c levels. Treatment with glargine was associated with lower fasting glucose values than treatment with detemir (8.1±1.5 vs. 8.2±1.7 mmol/L, p=0.01). Incidence rate of hypoglycemia was not different between insulin treatments (IRR=1.18, 95%CI 1.00-1.38; p=0.07). Detemir treatment was associated with a higher increase in body weight (p=0.008) and height (p=0.02) when compared with glargine. Detemir and glargine not show significant differential effects on the GH/IGFI axis. The greater weight gain and height associated with detemir treatment, apparently not related to the level of pubertal growth, deserve further investigation. © Georg Thieme Verlag KG Stuttgart · New York.
Yang, Qianlei; Cui, Yan; Luo, Fei; Liu, Xinlu; Wang, Qiushi; Bai, Jun; Dong, Faqin; Sun, Qian; Lu, Lu; Xu, Hui; Xue, Junchao; Chen, Chao; Xiang, Quanyong; Liu, Qizhan; Zhang, Qingbi
Cigarette smoke causes insulin resistance, which is associated with type 2 diabetes mellitus (T2DM). However, the mechanism by which this occurs remains poorly understood. Because the involvement of microRNAs (miRNAs) in the development of insulin resistance is largely unknown, we investigated, in hepatocytes, the roles of miR-191 in cigarette smoke extract (CSE)-induced insulin resistance. In L-02 cells, CSE not only decreased glucose uptake and glycogen levels but also reduced levels of insulin receptor substrate-1 (IRS-1) and Akt activation, effects that were blocked by SC79, an activator of Akt. CSE also increased miR-191 levels in L-02 cells. Furthermore, the inhibition of miR-191 blocked the decreases of IRS-1 and p-Akt levels, which antagonized the decreases of glucose uptake and glycogen levels in L-02 cells induced by CSE. These results reveal a mechanism by which miR-191 is involved in CSE-induced hepatic insulin resistance via the IRS-1/Akt signaling pathway, which helps to elucidate the mechanism for cigarette smoke-induced T2DM.
Full Text Available Exogenous insulin is the only treatment available for type 1 diabetic patients and is mostly administered by subcutaneous (SC injection in a basal and bolus scheme using insulin pens (injection or pumps (preimplanted SC catheter. Some divergence exists between these two modes of administration, since pumps provide better glycaemic control compared to injections in humans. The aim of this study was to compare the impacts of two modes of insulin administration (single injections of long-acting insulin or pump delivery of rapid-acting insulin at the same dosage (4 IU/200 g/day on rat metabolism and tissues. The rat weight and blood glucose levels were measured periodically after treatment. Immunostaining for signs of oxidative stress and for macrophages was performed on the liver and omental tissues. The continuous insulin delivery by pumps restored normoglycaemia, which induced the reduction of both reactive oxygen species and macrophage infiltration into the liver and omentum. Injections controlled the glucose levels for only a short period of time and therefore tissue stress and inflammation were elevated. In conclusion, the insulin administration mode has a crucial impact on rat metabolic parameters, which has to be taken into account when studies are designed.
Rabbone, Ivana; Barbetti, Fabrizio; Gentilella, Raffaella; Mossetto, Gilberto; Bonfanti, Riccardo; Maffeis, Claudio; Iafusco, Dario; Piccinno, Elvira
Neonatal diabetes mellitus (NDM) is a rare disorder, and guidance is limited regarding its optimal management. We reviewed insulin usage in NDM, with a focus on continuous subcutaneous insulin infusion (CSII). A PubMed search identified 40 reports of patients with NDM treated with insulin published between 1994 and 2016. Data concerning treatment of NDM are limited. CSII resolves some of the issues associated with insulin therapy in neonates. No clinical trials of CSII in NDM have been reported. Case reports suggest that CSII is a safe and effective means of treating NDM. CSII was initiated to improve glycaemic control, for practicality and convenience, and to overcome difficulties associated with the maintenance of long-term intravenous catheters. CSII can provide better glycaemic control than multiple daily injections, with few hypoglycaemic events. Continuous glucose monitoring integrated with the pump helps provide more precise control of blood glucose levels. CSII generally uses short-acting insulin or rapid-acting insulin analogues, and those that are approved for use in neonates appear to be appropriate for the treatment of NDM using an insulin pump. Information from case reports indicates that CSII is safe and effective for the management of NDM. Copyright © 2017 Elsevier B.V. All rights reserved.
Jeppesen, P B; Gregersen, S; Poulsen, C R; Hermansen, K
The natural sweetener stevioside, which is found in the plant Stevia rebaudiana Bertoni, has been used for many years in the treatment of diabetes among Indians in Paraguay and Brazil. However, the mechanism for the blood glucose-lowering effect remains unknown. To elucidate the impact of stevioside and its aglucon steviol on insulin release from normal mouse islets and the beta-cell line INS-1 were used. Both stevioside and steviol (1 nmol/L to 1 mmol/L) dose-dependently enhanced insulin secretion from incubated mouse islets in the presence of 16.7 mmol/L glucose (P diabetes mellitus.
de Jong, Josta; Garne, Ester; Wender-Ozegowska, Ewa
Insulin analogues are commonly used in pregnant women with diabetes. It is not known if the use of insulin analogues in pregnancy is associated with any higher risk of congenital anomalies in the offspring compared with use of human insulin. We performed a literature search for studies of pregnant...... women with pregestational diabetes using insulin analogues in the first trimester and information on congenital anomalies. The studies were analysed to compare the congenital anomaly rate among foetuses of mothers using insulin analogues with foetuses of mothers using human insulin. Of 29 studies, we...... included 1286 foetuses of mothers using short-acting insulin analogues with 1089 references of mothers using human insulin and 768 foetuses of mothers using long-acting insulin analogues with 685 references of mothers using long-acting human insulin (Neutral Protamine Hagedorn). The congenital anomaly rate...
Full Text Available Abstract Type 1 diabetes is one of the most common endocrine problems in childhood and adolescence, and remains a serious chronic disorder with increased morbidity and mortality, and reduced quality of life. Technological innovations positively affect the management of type 1 diabetes. Closed-loop insulin delivery (artificial pancreas is a recent medical innovation, aiming to reduce the risk of hypoglycemia while achieving tight control of glucose. Characterized by real-time glucose-responsive insulin administration, closed-loop systems combine glucose-sensing and insulin-delivery components. In the most viable and researched configuration, a disposable sensor measures interstitial glucose levels, which are fed into a control algorithm controlling delivery of a rapid-acting insulin analog into the subcutaneous tissue by an insulin pump. Research progress builds on an increasing use of insulin pumps and availability of glucose monitors. We review the current status of insulin delivery, focusing on clinical evaluations of closed-loop systems. Future goals are outlined, and benefits and limitations of closed-loop therapy contrasted. The clinical utility of these systems is constrained by inaccuracies in glucose sensing, inter- and intra-patient variability, and delays due to absorption of insulin from the subcutaneous tissue, all of which are being gradually addressed.
Feld, Gordon B; Wilhem, Ines; Benedict, Christian; Rüdel, Benjamin; Klameth, Corinna; Born, Jan; Hallschmid, Manfred
The neurochemical underpinnings of sleep's contribution to the establishment and maintenance of memory traces are largely unexplored. Considering that intranasal insulin administration to the CNS improves memory functions in healthy and memory-impaired humans, we tested whether brain insulin signaling and sleep interact to enhance memory consolidation in healthy participants. We investigated the effect of intranasal insulin on sleep-associated neurophysiological and neuroendocrine parameters and memory consolidation in 16 men and 16 women (aged 18-30 years), who learned a declarative word-pair task and a procedural finger sequence tapping task in the evening before intranasal insulin (160 IU) or placebo administration and 8 h of nocturnal sleep. On the subsequent evening, they learned interfering word-pairs and a new finger sequence before retrieving the original memories. Insulin increased growth hormone concentrations in the first night-half and EEG delta power during the second 90 min of non-rapid-eye-movement sleep. Insulin treatment impaired the acquisition of new contents in both the declarative and procedural memory systems on the next day, whereas retrieval of original memories was unchanged. Results indicate that sleep-associated memory consolidation is not a primary mediator of insulin's acute memory-improving effect, but that the peptide acts on mechanisms that diminish the subsequent encoding of novel information. Thus, by inhibiting processes of active forgetting during sleep, central nervous insulin might reduce the interfering influence of encoding new information.
Zhao, Yun; Tang, Zhuqi; Zhu, Xiaohui; Wang, Xueqin; Wang, Cuifang; Zhang, Wanlu; Xia, Nana; Wang, Suxin; Huang, Jieru; Cui, Shiwei
Insulin resistance is often accompanied by chronic inflammatory responses. The mitogen-activated protein kinase (MAPK) pathway is rapidly activated in response to many inflammatory cytokines. But the functional role of MAPKs in palmitate-induced insulin resistance has yet to be clarified. In this study, we found that transforming growth factor β-activated kinase binding protein-3 (TAB3) was up-regulated in insulin resistance. Considering the relationship between transforming growth factor β-activated kinase (TAK1) and MAPK pathway, we assumed TAB3 involved in insulin resistance through activation of MAPK pathway. To certify this hypothesis, we knocked down TAB3 in palmitate treated HepG2 cells and detected subsequent biological responses. Importantly, TAB3 siRNA directly reversed insulin sensitivity by improving insulin signal transduction. Moreover, silencing of TAB3 could facilitate hepatic glucose uptake, reverse gluconeogenesis and improve ectopic fat accumulation. Meanwhile, we found that the positive effect of knocking down TAB3 was more significant when insulin resistance occurred. All these results indicate that TAB3 acts as a negative regulator in insulin resistance through activation of MAPK pathway. Copyright © 2015 Elsevier Inc. All rights reserved.
M. F. Kalashnikova
Full Text Available Background: Maintenance of stable glycemic control is an important prerequisite of effective treatment of patients with type 1 diabetes mellitus (DM. The ultra-long-acting basal insulin degludec allows for reduction of glycemic variability and for a substantial reduction in the rates of hypoglycemia with equivalent glycemic control. Evaluation of the impact of this novel insulin on diabetes-dependent quality of life and patient satisfactions with the treatment is necessary for comprehensive assessment of treatment efficacy.Aim: To study changes of glycated hemoglobin (HbA1c, rates of hypoglycemia, diabetes-dependent quality of life and treatment satisfaction in patients with type 1 DM, who have been switched to insulin degludec.Materials and methods: This open 12-week observational comparative study included 25 patients with type 1 DM (median age, 36 [20; 63] years, who were switched to insulin degludec in combination with a ultra-short insulin analogue. The control group included 21 patients with type 1 DM (median age, 40 [23; 63] years, who continued their treatment with a long-acting insulin analogue glargine. At baseline and at week 12 after switching to insulin degludec, we assessed HbA1c level, mean insulin dose, depression score, diabetes-dependent quality of life and patient satisfaction with the treatment with the use of the Russian versions of the diabetes-specific questionnaires “Audit of Diabetes-Dependent Quality of life” (RuADDQoL, and “Diabetes Treatment Satisfaction Questionnaire” (DTSQ, respectively.Results: At 3 months, there was a significant reduction of the HbA1c levels in the main and the control groups to 7.57% (Ме 7.5 [7.1; 8.4]; р=0.03 and 8.18% (Ме 7.8% [7.4; 8.7]; р=0.04, respectively. The mean reduction of this parameter under treatment with degludec was slightly higher than under treatment with glargine (0.73 vs 0.57%, respectively, at 3 months the difference being statistically
Bajaj, Harpreet S; Venn, Karri; Ye, Chenglin; Aronson, Ronnie
Basal insulin titration in the real world is often unsuccessful. LTHome, a web tool, applies a rules engine-based algorithm providing insulin titration advice directly to the patient. This pilot, randomized trial evaluates basal insulin glargine titration by LTHome compared to enhanced usual therapy ([EUT]-diabetes education program) over 12 weeks. Important inclusion criteria: 18-75 years, type 2 diabetes, computer literacy, and HbA1c >7.0%. Trial protocol was approved by ethics board. We randomized 139 subjects. The achievement of primary composite outcome (four out of seven fasting plasma glucose [FPG] within 5-7.2 mmol/L + mean for three consecutive FPG within 5-7.2 mmol/L + no severe hypoglycemia) was 15% in LTHome versus 41% in EUT (noninferiority not met, P-value = 0.92). Other outcomes were similar between the LTHome and EUT arms: alternate composite outcome achievement (last five FPG mean within the range of 5-7.2 mmol/L + no hypoglycemia, 47% and 51%, P = 0.73); A1c reduction (-1.0% and -1.1%, P = 0.66); proportion achieving A1c ≤7% (14% and 20%, P = 0.36); and hypoglycemia incidence (31% and 37%, P = 0.4), respectively. Patient satisfaction score improvements were greater in LTHome versus EUT (change in fear of hypoglycemia score P = 0.04 and change in diabetes distress score P = 0.04). The mean number of additional healthcare provider visits was 0.13 for LTHome and 1.22 for EUT (P INNOVATE trial suggests clinical utility of LTHome compared to EUT in real-life settings. Further research is needed to evaluate the efficacy and safety of automated insulin titration algorithms.
Vincent, M; Nobécourt, E
Low-dose intravenous infusions of regular insulin, usually initiated in the emergency department and continued in the intensive care unit (ICU), are the standard care for patients with diabetic ketoacidosis (DKA) to ensure rapid resolution of hyperglycaemia and ketoacidosis. Several studies have evaluated whether subcutaneous injections of the rapid-acting analogue insulin lispro may be an alternative to intravenous insulin infusion for avoiding ICU admissions of uncomplicated DKA cases. This review summarizes the current clinical evidence for the effectiveness and safety of subcutaneous insulin lispro injections in non-severe DKA patients. Relevant studies were identified by a systematic literature search through the PubMed database. To date, four small randomized studies (156 patients overall; three studies in adults and one in paediatric patients with diabetes) have directly compared subcutaneous insulin lispro injections every 1-2h vs continuous intravenous infusions of regular insulin. Patients with severe complications were excluded. In all studies, the mean time to resolution of DKA was similar in both treatment groups [range (three studies): lispro 10-14.8h; regular insulin 11-13.2h]. The mean time to resolution of hyperglycaemia, total insulin doses required, number of hospitalization days and number of hypoglycaemic episodes were similar in both treatment groups; no severe complications or DKA recurrences were reported, and one study showed a 39% cost reduction for the insulin lispro group. In patients with mild-to-moderate DKA, subcutaneous injections of insulin lispro every 1-2h offer a feasible alternative to continuous intravenous infusions of regular insulin, and should now be evaluated in larger, more appropriately powered studies. Copyright © 2013. Published by Elsevier Masson SAS.
Berne, C; Wibell, L; Lindmark, G
Between 1975-1984, 119 women with gestational diabetes (GDM) were treated with insulin in Uppsala, representing a mean yearly incidence of 4.5/1,000 pregnancies. Women with GDM were older and more obese than the general pregnant population. Insulin treatment was instituted during a 5-7 day stay in hospital. The mean total daily dose of insulin prepartum, when fasting blood glucose had been normalized, was 53 (SD +/- 25) units (34 +/- 15 units of rapid-acting and 20 +/- 11 units of medium-acting insulin), divided into two doses daily. Mean duration of treatment was 6.4 weeks. The perinatal mortality was 0.8%, compared with 7.4% in previous pregnancies in the same women. The perinatal morbidity was generally mild and included hypoglycaemia (10.9%), hyperbilirubinaemia requiring treatment (2.5%), shoulder dystocia (2.5%) and one case of mild respiratory distress syndrome. The rate of macrosomia was reduced in the present pregnancies compared with previous ones in the women with GDM, but not abolished completely, probably because of too short a duration of improved metabolic control. Spontaneous delivery was favoured and the rate of Caesarean section was 13.5%. Thus, treatment with high doses of insulin in an unselected group of women with GDM is feasible. Normal perinatal mortality, reduced macrosomia, and no gross perinatal morbidity was found in the infants. Though the extent to which insulin treatment per se contributed to the favourable outcome is difficult to assess, it is suggested that the case for a high level of ambition for metabolic normalization in GDM should be a subject of further study.
Ness, Gene C., E-mail: firstname.lastname@example.org [Department of Molecular Medicine, College of Medicine, University of South Florida, Tampa, FL 33612 (United States); Edelman, Jeffrey L.; Brooks, Patricia A. [Department of Molecular Medicine, College of Medicine, University of South Florida, Tampa, FL 33612 (United States)
Highlights: Black-Right-Pointing-Pointer siRNAs to tristetraprolin blocks transcription of HMGR in vivo in rat liver. Black-Right-Pointing-Pointer siRNAs to tristetraprolin inhibits insulin activation of HMGR transcription. Black-Right-Pointing-Pointer Insulin acts to rapidly increase tristetraprolin in liver nuclear extracts. -- Abstract: Several AU-rich RNA binding element (ARE) proteins were investigated for their possible effects on transcription of hepatic 3-hydroxy-3-methyglutaryl coenzyme A reductase (HMGR) in normal rats. Using in vivo electroporation, four different siRNAs to each ARE protein were introduced together with HMGR promoter (-325 to +20) luciferase construct and compared to saline controls. All four siRNAs to tristetraprolin (TTP) completely eliminated transcription from the HMGR promoter construct. Since insulin acts to rapidly increase hepatic HMGR transcription, the effect of TTP siRNA on induction by insulin was tested. The 3-fold stimulation by insulin was eliminated by this treatment. In comparison, siRNA to AU RNA binding protein/enoyl coenzyme A hydratase (AUH) had no effect. These findings indicate a role for TTP in the insulin-mediated activation of hepatic HMGR transcription.
Bruxvoort, Katia J; Leurent, Baptiste; Chandler, Clare I R; Ansah, Evelyn K; Baiden, Frank; Björkman, Anders; Burchett, Helen E D; Clarke, Siân E; Cundill, Bonnie; DiLiberto, Debora D; Elfving, Kristina; Goodman, Catherine; Hansen, Kristian S; Kachur, S Patrick; Lal, Sham; Lalloo, David G; Leslie, Toby; Magnussen, Pascal; Mangham-Jefferies, Lindsay; Mårtensson, Andreas; Mayan, Ismail; Mbonye, Anthony K; Msellem, Mwinyi I; Onwujekwe, Obinna E; Owusu-Agyei, Seth; Rowland, Mark W; Shakely, Delér; Staedke, Sarah G; Vestergaard, Lasse S; Webster, Jayne; Whitty, Christopher J M; Wiseman, Virginia L; Yeung, Shunmay; Schellenberg, David; Hopkins, Heidi
Since 2010, the World Health Organization has been recommending that all suspected cases of malaria be confirmed with parasite-based diagnosis before treatment. These guidelines represent a paradigm shift away from presumptive antimalarial treatment of fever. Malaria rapid diagnostic tests (mRDTs) are central to implementing this policy, intended to target artemisinin-based combination therapies (ACT) to patients with confirmed malaria and to improve management of patients with nonmalarial fevers. The ACT Consortium conducted ten linked studies, eight in sub-Saharan Africa and two in Afghanistan, to evaluate the impact of mRDT introduction on case management across settings that vary in malaria endemicity and healthcare provider type. This synthesis includes 562,368 outpatient encounters (study size range 2,400-432,513). mRDTs were associated with significantly lower ACT prescription (range 8-69% versus 20-100%). Prescribing did not always adhere to malaria test results; in several settings, ACTs were prescribed to more than 30% of test-negative patients or to fewer than 80% of test-positive patients. Either an antimalarial or an antibiotic was prescribed for more than 75% of patients across most settings; lower antimalarial prescription for malaria test-negative patients was partly offset by higher antibiotic prescription. Symptomatic management with antipyretics alone was prescribed for fewer than 25% of patients across all scenarios. In community health worker and private retailer settings, mRDTs increased referral of patients to other providers. This synthesis provides an overview of shifts in case management that may be expected with mRDT introduction and highlights areas of focus to improve design and implementation of future case management programs.
King, George L.; Johnson, Sandra M.
Hormones such as insulin are transported from the interior to the exterior of blood vessels. Whether endothelial cells, which line the inner walls of blood vessels have a role in this transport of hormones is not clear, but it is known that endothelial cells can internalize and release insulin rapidly with little degradation. The transport of iodine-125-labeled insulin was measured directly through the use of dual chambers separated by a horizontal monolayer of cultured bovine aortic endothelial cells. In this setting, endothelial cells took up and released the labeled insulin, thereby transporting it across the cells. The transport of insulin across the endothelial cells was temperature sensitive and was inhibited by unlabeled insulin and by antibody to insulin receptor in proportion to the ability of these substances to inhibit insulin binding to its receptor. More than 80 percent of the transported insulin was intact. These data suggest that insulin is rapidly transported across endothelial cells by a receptor-mediated process.
Fiesselmann, Albrecht; Wiesner, Tobias; Fleischmann, Holger; Bramlage, Peter
The addition of a single injection of insulin to the oral drugs (basal supported oral therapy; BOT) has been shown to greatly reduce blood glucose levels. The intermediate-acting NPH insulin (NPH) and the long-acting insulin glargine (Lantus(®)) have been compared for use in BOT in numerous clinical trials; however, their efficacy and safety in a real-life setting have not been described. TIP (therapeutic benefits of patients on insulin glargine vs. NPH insulin being poorly controlled on prior short-time basal-insulin supported therapy with NPH insulin or insulin glargine) is a non-interventional, multicentre, observational study over 24 weeks. A total of 2629 patients were enrolled and 1931 were fully evaluable (1614 insulin glargine, 303 NPH insulin). Propensity scoring (PSM) was used to match 570 patients into 2 similar cohorts of 285 patients. In the PSM cohort, a slightly greater reduction in FBG and HbA1c levels was seen in the insulin glargine group compared to the NPH group. A weight loss, which was slightly more pronounced in insulin glargine patients despite receiving a lower insulin dose relative to the NPH group, was seen in both the groups. Additionally, hypoglycaemia, including nocturnal and severe events, was more prevalent in the patients receiving BOT with NPH. The occurrence of new micro- or macro-vascular complications and adverse events was low for both groups. A large proportion of patients changed from NPH therapy to insulin glargine therapy during the study, which was mainly attributable to insufficient glucose modulation. Improvements in quality of life and treatment satisfaction were found for both types of insulin. This observational study provides evidence from a real-life setting that BOT with insulin glargine provides slightly greater reductions in weight, FBG and HbA1c levels, with a lower risk of hypoglycaemia than patients receiving NPH. This conclusion indicates that insulin glargine may be preferable to NPH insulin for BOT.
Yu, Hanjie; Li, Mengmeng; Shen, Xinbei; Lv, Dan; Sun, Xin; Wang, Jinting; Gu, Xinmei; Hu, Jingning; Wang, Chuang
Previous studies have shown that a low dose of scopolamine produces rapid-acting antidepressant-like actions in rodents. Understanding the mechanisms underlying this effect and the dose-dependent variations of drug responses remains an important task. L-type voltage-dependent calcium channels were found to mediate rapid-acting antidepressant effects of certain medications (e.g., ketamine). Therefore, it is of great interest to determine the involvement of L-type voltage-dependent calcium channels in the action of scopolamine. Herein, we investigated the mechanisms underlying behavioral responses to various doses of scopolamine in mice to clarify the involvement of L-type voltage-dependent calcium channels in its modes of action. Open field test, novel object recognition test, and forced swimming test were performed on mice administered varied doses of scopolamine (0.025, 0.05, 0.1, 1, and 3 mg/kg, i.p.) alone or combined with L-type voltage-dependent calcium channel blocker verapamil (5 mg/kg, i.p.). Then, the changes in brain-derived neurotrophic factor and neuropeptide VGF (nonacronymic) levels in the hippocampus and prefrontal cortex of these mice were analyzed. Low doses of scopolamine (0.025 and 0.05 mg/kg) produced significant antidepressant-like effects in the forced swimming test, while higher doses (1 and 3 mg/kg) resulted in significant memory deficits and depressive-like behaviors. Moreover, the behavioral changes in responses to various doses may be related to the upregulation (0.025 and 0.05 mg/kg) and downregulation (1 and 3 mg/kg) of brain-derived neurotrophic factor and VGF in the hippocampus and prefrontal cortex in mice. We further found that the rapid-acting antidepressant-like effects and the upregulation on brain-derived neurotrophic factor and VGF produced by a low dose of scopolamine (0.025 mg/kg) were completely blocked by verapamil. These results indicate that L-type voltage-dependent calcium channels are likely involved in the behavioral
Zeng, Yi; Zhang, Le; Hu, Zhiping
Insulin performs unique non-metabolic functions within the brain. Broadly speaking, two major areas of these functions are those related to brain endothelial cells and the blood-brain barrier (BBB) function, and those related to behavioral effects, like cognition in disease states (Alzheimer's disease, AD) and in health. Recent studies showed that both these functions are associated with brain angiogenesis. These findings raise interesting questions such as how they are linked to each other and whether modifying brain angiogenesis by targeting certain insulin signaling pathways could be an effective strategy to treat dementia as in AD, or even to help secure healthy longevity. The two canonical downstream pathways involved in mediating the insulin signaling pathway, the phosphoinositide-3 kinase (PI3K), and mitogen-activated protein kinase (MAPK) cascades, in the brain are supposed to be similar to those in the periphery. PI3K and MAPK pathways play important roles in angiogenesis. Both are involved in stimulating hypoxia inducible factor (HIF) in angiogenesis and could be activated by the insulin signaling pathway. This suggests that PI3K and MAPK pathways might act as cross-talk between the insulin signaling pathway and the angiogenesis pathway in brain. But the cerebral insulin, insulin signaling pathway, and the detailed mechanism in the connection of insulin signaling pathway, brain angiogenesis pathway, and healthy aging or dementias are still mostly not clear and need further studies.
Aeberli, I.; Jung, A.; Murer, S.B.; Wildhaber, J.; Wildhaber-Brooks, J.; Knopfli, B.H.; Zimmermann, M.B.
Background: Although serum TSH is often elevated in obesity and may be linked to disorders of lipid and glucose metabolism, the clinical relevance of these relationships remains unclear. Subjects: Subjects were obese children and adolescents (n = 206; mean age 14 yr) undergoing rapid weight and fat
... involves changes in diet and lifestyle. The American Diabetes Association recommends losing excess weight, getting regular amounts of moderate intensity physical activity, and increasing dietary fiber to lower blood insulin levels and increase the ...
... to come strictly from animal sources (cow and pig pancreas cells). Most insulin used today is synthetic, ... developing type 2 diabetes , hypertension , hyperlipidemia , and/or heart disease several years down the road. Abdominal obesity, ...
Scharnagel, R; Kaiser, U; Schütze, A; Heineck, R; Gossrau, G; Sabatowski, R
Annually published data show a continual increase in the volume of opioid prescriptions in Germany, thus indicating an intensification of opioid therapy. The majority of opioids are prescribed to treat chronic non-cancer-related pain. On the basis of current guidelines, as well as in terms of the lack of data regarding long-term use of opioids and their effectiveness beyond a period of 3 months, this development must be viewed critically. With reference to four case reports, we discuss and evaluate opioid therapy in relation to medication misuse and the development of drug dependency. Particular emphasis is placed on the administration of rapid-release and short-acting opioid preparations, which we consider to be particularly problematic.
Moghimi, Hamid; Moradi, Amir; Hamedi, Javad; Basiri, Mina
Rapid, accurate, and easy identification of pathogenic agents has always been important in medicine, veterinary, and agriculture. The brown spot infection is among the most common diseases in tangerine caused by Alternaria alternata. Due to the existence of seven various pathotypes of A. alternata species, it is challenging and time consuming to detect a pathotype responsible for citrus brown spot. In this study, we were seeking a rapid and specific approach to identify the tangerine pathotype within the A. alternata-pathogenic species, using the loop-mediated isothermal amplification (LAMP) method and actts2 gene as a marker molecule. Nine pathogenic samples were obtained from the region of Ramsar, Iran, and certified as A. alternata-pathogenic isolates. Specific primers were designed for regions coding for Alternaria citri toxin (ACT), and the PCR and LAMP reactions were performed. Our data showed that the primers designed for the tangerine pathotype of A. alternata were specific, and in both reactions, positive results were only observed in desired pathotypes. In the other pathotypes of this species as well as other standard fungal samples as negative controls, no positive result was observed. Therefore, our results suggest the possibility to detect the tangerine-specific A. alternata pathotype from other related species with a high accuracy and in early stages of the disease.
Vestergaard, H; Andersen, P H; Lund, S
glycogen storage and glycolysis: glycogen synthase and phosphofructokinase, respectively. In nine diabetic patients biopsies of quadriceps muscle were taken before and 24-h after intensified insulin therapy and compared to findings in eight control subjects. Subcutaneous injections of rapid acting insulin...... diabetic patients showed a normal total glycogen synthase activity but a 48% decrease (p = 0.006) in glycogen synthase fractional velocity (0.1 mmol/l glucose 6-phosphate) (FV0.1) and a 45% increase (p = 0.01) in the half-maximal activation constant of glycogen synthase (A0.5). The activity...... of phosphofructokinase and the specific mRNA and immunoreactive protein levels of both glycogen synthase and phosphofructokinase were similar in the two groups. The 2.8-fold increase in serum insulin levels and the halving of the plasma glucose level for at least 15 h were associated with a normalization of glycogen...
Insulin antibodies - serum; Insulin Ab test; Insulin resistance - insulin antibodies; Diabetes - insulin antibodies ... You appear to have an allergic response to insulin Insulin no longer seems to control your diabetes
Full Text Available Ann Thompson,1 Patty Lathan,2 Linda Fleeman3 1School of Veterinary Science, The University of Queensland, Gatton, QLD, Australia; 2College of Veterinary Medicine Mississippi State University, Starkville, MS, USA; 3Animal Diabetes Australia, Melbourne, VIC, Australia Abstract: Insulin therapy is still the primary therapy for all diabetic dogs and cats. Several insulin options are available for each species, including veterinary registered products and human insulin preparations. The insulin chosen depends on the individual patient's requirements. Intermediate-acting insulin is usually the first choice for dogs, and longer-acting insulin is the first choice for cats. Once the insulin type is chosen, the best method of insulin administration should be considered. Traditionally, insulin vials and syringes have been used, but insulin pen devices have recently entered the veterinary market. Pens have different handling requirements when compared with standard insulin vials including: storage out of the refrigerator for some insulin preparations once pen cartridges are in use; priming of the pen to ensure a full dose of insulin is administered; and holding the pen device in place for several seconds during the injection. Many different types of pen devices are available, with features such as half-unit dosing, large dials for visually impaired people, and memory that can display the last time and dose of insulin administered. Insulin pens come in both reusable and disposable options. Pens have several benefits over syringes, including improved dose accuracy, especially for low insulin doses. Keywords: diabetes, mellitus, canine, feline, NPH, glargine, porcine lente
Strilka, Richard J; Stull, Mamie C; Clemens, Michael S; McCaver, Stewart C; Armen, Scott B
The critically ill can have persistent dysglycemia during the "subacute" recovery phase of their illness because of altered gene expression; it is also not uncommon for these patients to receive continuous enteral nutrition during this time. The optimal short-acting subcutaneous insulin therapy that should be used in this clinical scenario, however, is unknown. Our aim was to conduct a qualitative numerical study of the glucose-insulin dynamics within this patient population to answer the above question. This analysis may help clinicians design a relevant clinical trial. Eight virtual patients with stress hyperglycemia were simulated by means of a mathematical model. Each virtual patient had a different combination of insulin resistance and insulin deficiency that defined their unique stress hyperglycemia state; the rate of gluconeogenesis was also doubled. The patients received 25 injections of subcutaneous regular or Lispro insulin (0-6 U) with 3 rates of continuous nutrition. The main outcome measurements were the change in mean glucose concentration, the change in glucose variability, and hypoglycemic episodes. These end points were interpreted by how the ultradian oscillations of glucose concentration were affected by each insulin preparation. Subcutaneous regular insulin lowered both mean glucose concentrations and glucose variability in a linear fashion. No hypoglycemic episodes were noted. Although subcutaneous Lispro insulin lowered mean glucose concentrations, glucose variability increased in a nonlinear fashion. In patients with high insulin resistance and nutrition at goal, "rebound hyperglycemia" was noted after the insulin analog was rapidly metabolized. When the nutritional source was removed, hypoglycemia tended to occur at higher Lispro insulin doses. Finally, patients with severe insulin resistance seemed the most sensitive to insulin concentration changes. Subcutaneous regular insulin consistently lowered mean glucose concentrations and glucose
Catalano, Karyn J.; Maddux, Betty A.; Szary, Jaroslaw; Youngren, Jack F.; Goldfine, Ira D.; Schaufele, Fred
Insulin resistance, the diminished response of target tissues to insulin, is associated with the metabolic syndrome and a predisposition towards diabetes in a growing proportion of the worldwide population. Under insulin resistant states, the cellular response of the insulin signaling pathway is diminished and the body typically responds by increasing serum insulin concentrations to maintain insulin signaling. Some evidence indicates that the increased insulin concentration may itself further dampen insulin response. If so, insulin resistance would worsen as the level of circulating insulin increases during compensation, which could contribute to the transition of insulin resistance to more severe disease. Here, we investigated the consequences of excess insulin exposure to insulin receptor (IR) activity. Cells chronically exposed to insulin show a diminished the level of IR tyrosine and serine autophosphorylation below that observed after short-term insulin exposure. The diminished IR response did not originate with IR internalization since IR amounts at the cell membrane were similar after short- and long-term insulin incubation. Förster resonance energy transfer between fluorophores attached to the IR tyrosine kinase (TK) domain showed that a change in the TK domain occurred upon prolonged, but not short-term, insulin exposure. Even though the altered ‘insulin refractory’ IR TK FRET and IR autophosphorylation levels returned to baseline (non-stimulated) levels after wash-out of the original insulin stimulus, subsequent short-term exposure to insulin caused immediate re-establishment of the insulin-refractory levels. This suggests that some cell-based ‘memory’ of chronic hyperinsulinemic exposure acts directly at the IR. An improved understanding of that memory may help define interventions to reset the IR to full insulin responsiveness and impede the progression of insulin resistance to more severe disease states. PMID:25259572
Kodani, Noriko; Saisho, Yoshifumi; Tanaka, Kumiko; Kawai, Toshihide; Itoh, Hiroshi
The objective of this study was to clarify the effects of mitiglinide on daily glycemic variability and oxidative stress markers in outpatients with type 2 diabetes mellitus that is insufficiently controlled by diet and/or non-insulin secretagogues. We enrolled 24 patients with type 2 diabetes whose glycemic control had been suboptimal [i.e. glycosylated hemoglobin (HbA(1c)) ≥ 6.9 %]. The patients were treated with mitiglinide 10 mg three times daily for 16 weeks. If their glycemic control was not improved at week 8, the dose of mitiglinide was increased to 20 mg three times daily. Daily glycemic variability was assessed by 7-point self-monitoring of blood glucose for 2 days, and standard deviation (SD), M value, and mean of daily differences(MODD) were calculated. Oxidative stress was assessed by oxidized low-density lipoprotein, pentosidine,urinary 8-iso-prostaglandin F2 alpha, and urinary 8-hydroxydeoxy guanosine. After 16 weeks of mitiglinide treatment, the HbA(1c) level was significantly decreased (mean ± SD,7.4 ± 0.7 to 6.8 ± 0.5 %, P oxidative stress markers. The present study supports the notion that mitiglinide improves postprandial glucose excursion and HbA(1c) level in patients with type 2 diabetes. In addition,we demonstrated that mitiglinide also effectively improves daily glycemic variability. The effect of mitiglinide on oxidative stress needs further investigation.
... in the abdomen just behind the stomach, produces insulin. Insulin is a hormone that takes glucose from the ... occurs when the pancreas does not produce enough insulin or when the body doesn’t use insulin ...
... After Your Baby is Born Monogenic Diabetes Prediabetes & Insulin Resistance What is insulin? Insulin is a hormone made in the pancreas, ... body absorb glucose and use it for energy. Insulin's Role in Blood Glucose Control When blood glucose ...
Gomes, Marilia Brito; Rodacki, Melanie; Pavin, Elizabeth João; Cobas, Roberta Arnoldi; Felicio, João S; Zajdenverg, Lenita; Negrato, Carlos Antonio
Establish the relationship between demographic, educational and economic status on insulin therapeutic regimens (ITRs) and on glycemic control in patients with type 1 diabetes. This was a cross-sectional, multicenter study with 1760 patients conducted between August 2011 and August 2014 in 10 Brazilian cities. Patients were stratified according to ITRs as follows: only NPH insulin (group 1, n=80(4.5%)); only long-acting insulin analogs (group 2, n=6(0.3%)); continuous subcutaneous insulin infusion (CSII) (group 3, n=62(3.5%)); NPH plus regular insulin (group 4, n=710(40.3%)); NPH plus ultra-rapid insulin analogs (group 5, n=259(14.8%)); long-acting insulin analogs plus regular insulin (group 6, n=25(4.4%)) and long-acting plus ultra-rapid insulin analogs (group 7, n=618 (35.1%)). As group A (provided free of charge by the government) we considered groups 1 and 4, and as group B (obtained through lawsuit or out-of-pocket) groups 2, 3 and 7. Multivariate logistic analysis showed that independent variables related to group B were older age, more years of school attendance, higher economic status and ethnicity (Caucasians). The independent variables related to better glycemic control were older age, higher adherence to diet, higher frequency of self-monitoring of blood glucose, more years of school attendance and belonging to group B. In Brazilian National Health Care System, prescriptions of insulin analogs or CSII are more frequent in Caucasian patients with type 1 diabetes, with higher economic status and more years ofschool attendance. Among these variables years of school attendance was the only one associated with better glycemic control. Copyright © 2017 Elsevier B.V. All rights reserved.
Full Text Available Abstract Background Children with type 1 diabetes (DM1 often use three daily (TID injections with intermediate acting insulin at breakfast and bedtime, and rapid acting insulin at breakfast and dinner. Substituting the evening intermediate acting insulin with a long acting insulin analogue (LAIA at dinner in a twice daily (BID injection regimen may be as effective as a TID regimen. The objective of this pilot study was to compare HbA1c in children with DM1 using a BID regimen with a LAIA at dinner (intervention to those using a standard TID regimen (control over 6 months. Methods Randomized controlled trial with main outcome measure being HbA1c at 0, 3 and 6 months. Secondary outcomes were frequency of adverse events (hypoglycemia, diabetic ketoacidosis, weight gain and scores on the Diabetes Quality of Life Measure for Youth (DQOLY. Results 18 subjects (10 control, 8 intervention. Mean years (standard deviations for control and intervention respectively were: age at diagnosis of DM1 6.31 (2.91 vs 7.76 (3.22, duration of DM1 5.96 (4.95 vs 3.76 (3.37. No significant differences were seen in the mean HbA1c between control and intervention at 0 months [8.48(0.86 vs 8.57(1.13], 3 months [8.47(0.50 vs 7.99(0.61], or 6 months [8.42(0.63 vs 8.30(0.76]. No significant differences were found between groups for frequency of adverse events or DQOLY. Conclusions In this pilot study, incorporating LAIA in a BID regimen did not cause deterioration in HbA1c or increases in adverse events; suggesting that this may be a viable option for families where a more simplified insulin regimen would be beneficial and compliance may be improved. Trial registration ClinicalTrials.gov: NCT00522210
Full Text Available Abstract Centrally administered insulin-like growth factor (IGF-I has anti-depressant activity in several rodent models, including lipopolysaccharide (LPS-induced depression. In this study we tested the ability of IGF-I and GPE (the N-terminal tri-peptide derived from IGF-I to alter depression-like behavior induced by intraperitoneal (i.p. administration of LPS in a preventive and curative manner. In the first case, IGF-I (1 μg or GPE (5 μg was administered i.c.v. to CD-1 mice followed 30 min later by 330 μg/kg body weight i.p. LPS. In the second case, 830 μg/kg body weight LPS was given 24 h prior to either IGF-I or GPE. When administered i.p., LPS induced full-blown sickness assessed as a loss of body weight, decrease in food intake and sickness behavior. None of these indices were affected by IGF-I or GPE. LPS also induced depression-like behavior; assessed as an increased duration of immobility in the tail suspension and forced swim tests. When administered before or after LPS, IGF-I and GPE abrogated the LPS response; attenuating induction of depression-like behaviors and blocking preexistent depression-like behaviors. Similar to previous work with IGF-I, GPE decreased brain expression of cytokines in response to LPS although unlike IGF-I, GPE did not induce the expression of brain-derived neurotrophic factor (BDNF. LPS induced expression of tryptophan dioxygenases, IDO1, IDO2 and TDO2, but expression of these enzymes was not altered by GPE. Thus, both IGF-I and GPE elicit specific improvement in depression-like behavior independent of sickness, an action that could be due to their anti-inflammatory properties.
Jensen, Benjamin Anderschou Holbech
Insulin resistance (IR) is escalating with alarming pace and is no longer restricted to westernized countries. As a forerunner for some of the most serious threats to human health including metabolic syndrome, cardiovascular diseases, and type 2-diabetes, the need for new treatment modalities...
Wollmer, Per; Pieber, Thomas R; Gall, Mari-Anne; Brunton, Stephen
Inhaled insulin has recently emerged as an alternative to subcutaneous insulin administration. One inhaled insulin device, AERx (a registered trademark of Aradigm Corp., Hayward, CA, or its affiliates in the United States and other countries) insulin diabetes management system (iDMS) (Novo Nordisk A/S, Bagsvaerd, Denmark), uses a unique liquid human insulin strip to deliver an aerosol of insulin to the lungs. AERx iDMS enables 1-unit increment dosing, and the device ensures that the insulin dose is released at the optimal point of inhalation for delivery to the lungs. Compared with subcutaneous human insulin, the pharmacokinetic and pharmacodynamic profile of inhaled insulin with AERx iDMS is similar, but with a more rapid onset of action. Data from these pharmacokinetic studies have also demonstrated that inhaled insulin dosing with AERx iDMS is as consistent and reproducible as subcutaneous human insulin. In individuals with diabetes, prandial inhaled insulin with AERx iDMS is as effective and well tolerated as subcutaneous prandial human insulin or insulin aspart in terms of glycemic control and overall hypoglycemia. No major safety concerns have been raised with respect to pulmonary function tests. Other clinical studies using AERx iDMS in special populations, such as smokers, people with asthma, or people suffering from upper respiratory tract infections, have provided important information regarding the use of inhaled insulin in these circumstances. Overall, pulmonary insulin delivery with the AERx iDMS device appears to be a promising safe and efficacious alternative to subcutaneous insulin injections.
Pesić, Milica; Zivić, Sasa; Radenković, Sasa; Velojić, Milena; Dimić, Dragan; Antić, Slobodan
Insulin glargine is a long-acting insulin analog that mimics normal basal insulin secretion without pronounced peaks. The aim of this study was to compare insulin glargine with isophane insulin (NPH insulin) for basal insulin supply in patients with type 1 diabetes. A total of 48 type 1 diabetics on long term conventional intensive insulin therapy (IT) were randomized to three different regimens of basal insulin substitution: 1. continuation of NPH insulin once daily at bedtime with more intensive selfmonitoring (n = 15); 2. NPH insulin twice daily (n = 15); 3. insulin glargine once daily (n = 18). Meal time insulin aspart was continued in all groups. Fasting blood glucose (FBG) was lower in the glargine group (7.30+/-0.98 mmol/1) than in the twice daily NPH group (7.47+/-1.06 mmol/1), but without significant difference. FBG was significantly higher in the once daily NPH group (8.44+/-0.85 mmol/l; p < 0.05). HbAlc after 3 months did not change in the once daily NPH group, but decreased in the glargine group (from 7.72+/-0.86% to 6.87+/-0.50%), as well as in the twice daily NPH group (from 7.80+/-0.83% to 7.01+/-0.63%). Total daily insulin doses were similar in all groups but only in the glargine group there was an increase of basal and decrease of meal related insulin doses. The frequency of mild hypoglycemia was significantly lower in the glargine group (6.56+/-2.09) than in both NPH groups (9.0+/-1.65 in twice daily NPH group and 8.13+/-1.30 in other NPH group) (episodes/patients-month, p < 0.05). Basal insulin supplementation in type 1 diabetes mellitus with either twice daily NPH insulin or glargine can result in similar glycemic control when combined with meal time insulin aspart. However, with glargine regimen FBG, HbAlc and frequency of hypoglycemic event are lower. These facts contribute to better patients satisfaction with insulin glargine versus NPH insulin in IIT in type 1 diabetics.
Full Text Available Background/Aim. Insulin glargine is a long-acting insulin analog that mimics normal basal insulin secretion without pronounced peaks. The aim of this study was to compare insulin glargine with isophane insulin (NPH insulin for basal insulin supply in patients with type 1 diabetes. Methods. A total of 48 type 1 diabetics on long term conventional intensive insulin therapy (IIT were randomized to three different regimens of basal insulin substitution: 1. continuation of NPH insulin once daily at bedtime with more intensive selfmonitoring (n = 15; 2. NPH insulin twice daily (n = 15; 3. insulin glargine once daily (n = 18. Meal time insulin aspart was continued in all groups. Results. Fasting blood glucose (FBG was lower in the glargine group (7.30±0.98 mmol/l than in the twice daily NPH group (7.47±1.06 mmol/l, but without significant difference. FBG was significantly higher in the once daily NPH group (8.44±0.85 mmol/l; p < 0.05. HbA1c after 3 months did not change in the once daily NPH group, but decreased in the glargine group (from 7.72±0.86% to 6.87±0.50%, as well as in the twice daily NPH group (from 7.80±0.83% to 7.01±0.63%. Total daily insulin doses were similar in all groups but only in the glargine group there was an increase of basal and decrease of meal related insulin doses. The frequency of mild hypoglycemia was significantly lower in the glargine group (6.56±2.09 than in both NPH groups (9.0±1.65 in twice daily NPH group and 8.13±1.30 in other NPH group (episodes/patients-month, p < 0.05. Conclusion. Basal insulin supplementation in type 1 diabetes mellitus with either twice daily NPH insulin or glargine can result in similar glycemic control when combined with meal time insulin aspart. However, with glargine regimen FBG, HbA1c and frequency of hypoglycemic event are lower. These facts contribute to better patients satisfaction with insulin glargine versus NPH insulin in IIT in type 1 diabetics.
Lustig, R H; Greenway, F; Velasquez-Mieyer, P; Heimburger, D; Schumacher, D; Smith, D; Smith, W; Soler, N; Warsi, G; Berg, W; Maloney, J; Benedetto, J; Zhu, W; Hohneker, J
To compare changes in weight in obese patients who received long-acting octreotide (octreotide LAR) at one of three dose levels (20, 40, or 60 mg) or placebo over 6 months and to identify the lowest dose of octreotide LAR that safely achieved optimal weight loss. Randomized, double-blind, placebo-controlled trial of octreotide LAR at three dose levels. A total of 172 adults (28 men and 144 women) with at least moderate obesity (body mass index (BMI) range 30-65 kg/m2) and evidence of insulin hypersecretion were enrolled. Patients were predominantly either Caucasian (50.0%) or African American (45.3%). The mean age (38 +/- 11 year), weight (110.7 +/- 23 kg), and BMI (39.8 +/- 6.5 kg/m2) were similar across the four treatment groups. Efficacy measures included weight, BMI, fasting serum glucose; triglycerides; percentage of total body fat and abdominal fat as measured by dual-energy X-ray absorptiometry; skin fold thickness; waist-to-hip circumference; leptin; percentage of carbohydrates, fat, and protein ingested; nutritional evaluation (including dietary analysis--3-day food record); quality of life (QoL; using the Impact of Weight on Quality of Life-Lite); Beck Depression Inventory; and Carbohydrate Craving Questionnaire. Safety measures included medical history, vital signs, physical examinations, hematology, blood chemistries, thyroid function tests, hemoglobin A1c, gallbladder ultrasound, electrocardiograms, and adverse events. After 6 months of treatment, patients receiving 40 or 60 mg of octreotide LAR experienced statistically significant weight loss compared to baseline, with mean differences from placebo in percent weight change of -1.98 and -1.87%, respectively. This finding was accompanied by statistically significant mean decreases in BMI compared to baseline, that is, a mean decrease of 0.73 and 0.79 kg/m2 for the 40 and 60 mg treatment arms, respectively. The observed weight loss was progressive during the 6-month treatment in the two higher dose
Bedinger, Daniel H; Adams, Sean H
Insulin acts as the major regulator of the fasting-to-fed metabolic transition by altering substrate metabolism, promoting energy storage, and helping activate protein synthesis. In addition to its glucoregulatory and other metabolic properties, insulin can also act as a growth factor. The metabolic and mitogenic responses to insulin are regulated by divergent post-receptor signaling mechanisms downstream from the activated insulin receptor (IR). However, the anabolic and growth-promoting properties of insulin require tissue-specific inter-relationships between the two pathways, and the nature and scope of insulin-regulated processes vary greatly across tissues. Understanding the nuances of this interplay between metabolic and growth-regulating properties of insulin would have important implications for development of novel insulin and IR modulator therapies that stimulate insulin receptor activation in both pathway- and tissue-specific manners. This review will provide a unique perspective focusing on the roles of "metabolic" and "mitogenic" actions of insulin signaling in various tissues, and how these networks should be considered when evaluating selective pharmacologic approaches to prevent or treat metabolic disease. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
Simon, A. C. R.; Holleman, F.; Hoekstra, J. B.; de Clercq, P. A.; Lemkes, B. A.; Hermanides, J.; Peek, N.
Insulin is the most potent agent for the treatment of diabetes mellitus. However insulin treatment requires frequent evaluation of blood glucose levels and adjustment of the insulin dose. This process is called titration. To guide patients with type 2 diabetes using once-daily long-acting insulin,
Kolka, Cathryn M; Castro, Ana Valeria B; Kirkman, Erlinda L; Bergman, Richard N
Insulin injected directly into skeletal muscle diffuses rapidly through the interstitial space to cause glucose uptake, but this is blocked in insulin resistance. As glucotoxicity is associated with endothelial dysfunction, the observed hyperglycemia in diet-induced obese dogs may inhibit insulin access to muscle cells, and exacerbate insulin resistance. Here we asked whether interstitial insulin diffusion is reduced in modest hyperglycemia, similar to that induced by a high fat diet. During normoglycemic (100 mg/dl) and moderately hyperglycemic (120 mg/dl) clamps in anesthetized canines, sequential doses of insulin were injected into the vastus medialis of one hindlimb; the contra-lateral limb served as a control. Plasma samples were collected and analyzed for insulin content. Lymph vessels of the hind leg were also catheterized, and lymph samples were analyzed as an indicator of interstitial insulin concentration. Insulin injection increased lymph insulin in normoglycemic animals, but not in hyperglycemic animals. Muscle glucose uptake was elevated in response to hyperglycemia, however the insulin-mediated glucose uptake in normoglycemic controls was not observed in hyperglycemia. Modest hyperglycemia prevented intra-muscularly injected insulin from diffusing through the interstitial space reduced insulin-mediated glucose uptake. Hyperglycemia prevents the appearance of injected insulin in the interstitial space, thus reducing insulin action on skeletal muscle cells. Copyright © 2015 Elsevier Inc. All rights reserved.
Radosavljević, Tatjana; Todorović, Vera; Sikić, Branka
REGULATION OF INSULIN SECRETION: Beta cells are unique endocrine cells. They respond positively, in terms of insulin secretion, not only to changes in the extracellular glucose concentration, but also to activators of the phospholipase C (cholecystokinin or acetylcholine), and to activators of adenylate cyclase (glucagon, glucagon-like peptide-1, or gastric inhibitory polypeptide). Major messengers which mediate glucose action for insulin release are Ca2+, adenosine triphosphate (ATP) and diacylglycerol (DAG). MAJOR PATHWAYS OF INSULIN RELEASE STIMULATION: There are four major pathways involved in stimulation of insulin release. The first pathway is KATP channel-dependent pathway in which increased blood glucose concentrations and increased b-cell metabolism result in a change in intracellular ATP/ADP ratio. This is a contributory factor in closure of ATP-dependent K+ channels, depolarization of b-cell membrane, in increased voltage-dependent L-type Ca2+ channel activity. Increased Ca2+ influx results in increased intracellular Ca2+ and stimulated insulin release. KATP channel-independent pathway augments Ca(2+) -stimulated insulin secretion of KATP channel-dependent pathway. Major potentiation of release results from hormonal and peptidergic activation of receptors linked to adenylyl cyclase. Adenylyl cyclase activity is stimulated by hormones such as vasoactive intestinal peptide (VIP), glucagon-like peptide-1 (GLP-1), and so on. These hormones, acting via G protein, stimulate adenylyl cyclase, thus causing a rise in cyclic adenosine monophosphate (cAMP) and activation of protein kinase A (PKA). Increased activity of PKA results in potentiation of insulin secretion.
Galan, B.E. de; Simsek, S.; Tack, C.J.J.; Heine, R.J.
Many patients with diabetes mellitus view subcutaneous injections of insulin as a daily burden. Pulmonary delivery of insulin offers an alternative route of administration and may as such improve diabetes treatment. Inhaled insulin provides a rapid absorption of insulin, but with low
Full Text Available Abstract Background The uncertainties regarding dose similarities between basal long-acting insulin analogues remain. Recent real-world studies indicate dose similarities between insulin detemir and insulin glargine, but further studies are still warranted. The aim of this study was to compare real-life daily doses of insulin detemir and insulin glargine in type 2 diabetes patients when administered once daily. Methods We analysed 536 patient cases from general practice (63% and endocrinological outpatient clinics (37%. A self-administered questionnaire completed by the treating physician was used to obtain data on patient characteristics (gender, age, weight, height, latest HbA1c-value, daily doses, administration of and number of years treated with insulin detemir and insulin glargine, concomitant insulin use and use of non-insulin anti-diabetic medication. Both bivariate analyses and multivariate regression analyses were applied to examine whether there were differences in the daily doses of insulin detemir and insulin glargine. Results There was no significant difference in the mean daily doses of insulin detemir (0.414 U/kg and insulin glargine (0.416 U/kg (p = 0.4341. In multivariate regression analyses, age and BMI had a significant influence on daily insulin dose with the dose increasing 0.003 U/kg (p = 0.0375 and 0.008 U/kg (p = 0.0003 with every 1 increment in age and BMI, respectively. Conclusions Dose similarities between insulin detemir and insulin glargine were seen in type 2 diabetes patients when administered once daily. Thus, the use of insulin detemir and insulin glargine is not associated with different medical costs if the price and treating algorithm are similar.
Jensen, Benjamin Anderschou Holbech
Insulin resistance (IR) is escalating with alarming pace and is no longer restricted to westernized countries. As a forerunner for some of the most serious threats to human health including metabolic syndrome, cardiovascular diseases, and type 2-diabetes, the need for new treatment modalities...... with IR independent of weight gain. In conclusion, the data presented in the current thesis, supported by a thorough review of available literature, advocate that 1) Inflammation is a triggering event fueling IR; 2) Commensal microbes can, when mistreated, aggravate IR and glucose intolerance; and 3) Diet...
Kim, Jung; Bilder, David; Neufeld, Thomas P
Insulin resistance, the failure to activate insulin signaling in the presence of ligand, leads to metabolic diseases, including type 2 diabetes. Physical activity and mechanical stress have been shown to protect against insulin resistance, but the molecular mechanisms remain unclear. Here, we address this relationship in the Drosophila larval fat body, an insulin-sensitive organ analogous to vertebrate adipose tissue and livers. We found that insulin signaling in Drosophila fat body cells is abolished in the absence of physical activity and mechanical stress even when excess insulin is present. Physical movement is required for insulin sensitivity in both intact larvae and fat bodies cultured ex vivo. Interestingly, the insulin receptor and other downstream components are recruited to the plasma membrane in response to mechanical stress, and this membrane localization is rapidly lost upon disruption of larval or tissue movement. Sensing of mechanical stimuli is mediated in part by integrins, whose activation is necessary and sufficient for mechanical stress-dependent insulin signaling. Insulin resistance develops naturally during the transition from the active larval stage to the immotile pupal stage, suggesting that regulation of insulin sensitivity by mechanical stress may help coordinate developmental programming with metabolism. © 2018 Kim et al.; Published by Cold Spring Harbor Laboratory Press.
. This is probably the main explanation for the absence of improvement in overall glycaemic control when compared with regular human insulin. A tendency to a reduction in hypoglycaemic events during treatment with fast-acting analogues has been observed in most studies. Recent studies have indicated that NPH insulin...... in a long half-life with a residual activity of about 50% 24 h after injection. Insulin glargine is a peakless insulin and studies in both type 1 and type 2 diabetic patients indicate that glargine improves fasting blood glucose control and reduces the incidence of nocturnal hypoglycaemia. Surprisingly...
de Luca, Carl; Olefsky, Jerrold M.
Obesity-induced chronic inflammation is a key component in the pathogenesis of insulin resistance and the Metabolic syndrome. In this review, we focus on the interconnection between obesity, inflammation and insulin resistance. Pro-inflammatory cytokines can cause insulin resistance in adipose tissue, skeletal muscle and liver by inhibiting insulin signal transduction. The sources of cytokines in insulin resistant states are the insulin target tissue themselves, primarily fat and liver, but t...
Bindu I Somarajan
Full Text Available Many neurodegenerative disorders are associated with rapid eye movement sleep (REMS-loss, however the mechanism was unknown. As REMS-loss elevates noradrenaline (NA level in the brain as well as induces neuronal apoptosis and degeneration, in this study we have delineated the intracellular molecular pathway involved in REMS deprivation (REMSD associated NA-induced neuronal apoptosis. Rats were REMS deprived for 6 days by the classical flower-pot method, suitable controls were conducted and the effects on apoptosis markers evaluated. Further, the role of NA was studied by one, intraperitoneal (i.p. injection of NA-ergic alpha1-adrenoceptor antagonist prazosin (PRZ and two, by down-regulation of NA synthesis in locus coeruleus (LC neurons by local microinjection of tyrosine hydroxylase siRNA (TH-siRNA. Immunoblot estimates showed that the expressions of pro-apoptotic proteins viz. Bcl2-associated death promoter (BAD protein, apoptotic protease activating factor-1 (Apaf-1, cytochrome c, caspase9, caspase3 were elevated in the REMS-deprived rat brains, while caspase8 level remained unaffected; PRZ treatment did not allow elevation of these pro-apoptotic factors. Further, REMSD increased cytochrome c expression, which was prevented if the NA synthesis from the LC neurons was blocked by microinjection of TH-siRNA in vivo into the LC during REMSD in freely moving normal rats. Mitochondrial damage was re-confirmed by transmission electron microscopy (TEM, which showed distinctly swollen mitochondria with disintegrated cristae, chromosomal condensation and clumping along the nuclear membrane and all these changes were prevented in PRZ treated rats. Combining findings of this study along with earlier reports we propose that upon REMSD NA level increases in the brain as the LC NA-ergic REM-OFF neurons do not cease firing and TH is up-regulated in those neurons. This elevated NA acting on alpha1-adrenoceptors damages mitochondria causing release of
Full Text Available We report a 27-year-old paramedical lady with no known comorbidities, who presented with rapid-onset coma with hypoglycemia (plasma glucose at admission was 35 mg/dL. Clinical alertness suspected and confirmed the diagnosis of exogenous insulin administration probably with suicidal intent. During the course of her ICU stay, she developed bradycardia and hypotension which required ionotropic support. She remained in coma for 90 hours. A total of 470 g of dextrose was infused until she regained consciousness. No other complications of insulin overdose were observed during her stay in the hospital. Recovery was complete without any residual neurological deficits. Insulin administration should be kept in differential diagnosis when any case presents with coma and hypoglycemia, especially in paramedical personnel.
Andréia Cristina Conegero Sanches
Full Text Available All patients with Diabetes Mellitus (DM receive insulin therapy. In this study, we evaluated the efficacy, safety and tolerability of human insulin and insulin analogues. We performed a systematic review of the literature and a meta-analysis according to the Cochrane Collaboration methodology. In the absence of clinical studies comparing insulins, we performed a mixed treatment comparison to establish the differences between the active treatments. We included studies published from 1995 to 2010. HbA1c results, episodes of hypoglycemia and nocturnal hypoglycemia data were extracted and analyzed. Thirty-five randomized clinical trials were selected after examining the abstract and a full text review. These studies included 4,206 patients who received long-acting insulin analogues and 5,733 patients who received short-acting insulin analogues. Pooled data regarding efficacy indicated no significant differences in HbA1c values between glargine or detemir (once daily and NPH insulin. However, a twice-daily dose of detemir produced differences in HbA1c values that favored detemir (-0.14% [95% CI: -0.21 to -0.08]; p<0.0001; I²=0%. Direct and indirect comparisons are consistent and show that there were no significant differences between human insulin and insulin analogues in efficacy or safety. Our results indicate that long- and short-acting insulin analogues offer few clinical advantages over conventional human insulin.
Raj, N K Kavitha; Sharma, Chandra P
Diabetes mellitus is generally controlled quite well with the administration of oral medications or by the use of insulin injections. The current practice is the use of one or more doses, intermediate or long acting insulin per day. Oral insulin is a promising yet experimental method providing tight glycemic control for patients with diabetes. A biologically adhesive delivery systems offer important advantage over conventional drug delivery systems. The engineered polymer microspheres made of erodable polymer display strong adhesive interactions with gastrointestinal mucus and cellular lining can traverse both the mucosal epithelium and the follicle associated epithelium covering the lymphoid tissue of Peyer's patches. Alginate, a natural polymer recovered from seaweed is being developed as a nanoparticle for the delivery of insulin without being destroyed in the stomach. Alginate is in fact finding application in biotechnology industry as thickening agent, a gelling agent and a colloid stabilizer. Alginate has in addition, several other properties that have enabled it to be used as a matrix for entrapment and for the delivery of a variety of proteins such as insulin and cells. These properties include: a relatively inert aqueous environment within the matrix; a mild room temperature encapsulation process free of organic solvents; a high gel porosity which allows for high diffusion rates of macromolecules; the ability to control this porosity with simple coating procedures and dissolution and biodegradation of the system under normal physiological conditions.
Liñana, J J; Montoro, F J; Hernández, M D; Basomba, A
The prevalence of allergic reactions to insuline has decreased during the last few years. Probably this is due to the use of the newly-developed recombinant human insuline. At present, adverse reactions to insuline occur in 5-10% of patients on therapy with insuline. Adverse reactions may be local (more frequent) or systemic (rare). Insuline resistance consists in a different type of immunological reaction. Diagnosis of allergy to insuline is based on clinical history and cutaneous and serological tests. Treatment depends upon the severity of the reaction. When insuline is indispensable despite a previous allergic reaction, a desensitization protocol may be implemented.
Wollen, N; Bailey, C J
The interaction of metformin and insulin in the control of hepatic gluconeogenesis was examined in isolated hepatocytes from 48h starved rats using lactate (10(-2) mol/l) with pyruvate (10(-3) mol/l) as substrate. During 1 h incubations in the absence of added insulin, 10(-2) and 10(-3) mol/l metformin reduced gluconeogenesis by 65% and 59% respectively, but lower concentrations of metformin were not effective. Insulin alone (10(-6)-10(-8) mol/l) reduced (37%-16%) gluconeogenesis. The effect of insulin was enhanced (further reductions of 11%-24%) by 5 x 10(-4) mol/l metformin, although this concentration of metformin was not effective in the absence of insulin. At lower insulin concentrations (10(-9) and 10(-10) mol/l) which did not significantly affect gluconeogenesis alone, 5 x 10(-4) mol/l metformin decreased gluconeogenesis (32% and 28% respectively). At 10(-10) mol/l insulin, metformin concentrations of 10(-3)-10(-7) mol/l decreased gluconeogenesis by 60-20%. The results suggest that therapeutic concentrations of metformin may act synergistically with physiological concentrations of insulin to suppress hepatic gluconeogenesis.
Aravinthan, Aloysious [Division of Gastroenterology and Hepatology, Department of Medicine, University of Cambridge, Cambridge (United Kingdom); Challis, Benjamin [Institute of Metabolic Sciences, University of Cambridge, Cambridge (United Kingdom); Shannon, Nicholas [Cancer Research UK Cambridge Institute, Cambridge (United Kingdom); Hoare, Matthew [Division of Gastroenterology and Hepatology, Department of Medicine, University of Cambridge, Cambridge (United Kingdom); Cancer Research UK Cambridge Institute, Cambridge (United Kingdom); Heaney, Judith [Division of Gastroenterology and Hepatology, Department of Medicine, University of Cambridge, Cambridge (United Kingdom); Foundation for Liver Research, Institute of Hepatology, London (United Kingdom); Alexander, Graeme J.M., E-mail: email@example.com [Division of Gastroenterology and Hepatology, Department of Medicine, University of Cambridge, Cambridge (United Kingdom)
Insulin resistance has been described in association with chronic liver disease for decades. Hepatocyte senescence has been demonstrated in chronic liver disease and as many as 80% of hepatocytes show a senescent phenotype in advanced liver disease. The aim of this study was to understand the role of hepatocyte senescence in the development of insulin resistance. Senescence was induced in HepG2 cells via oxidative stress. The insulin metabolic pathway was studied in control and senescent cells following insulin stimulation. GLUT2 and GLUT4 expressions were studied in HepG2 cells and human liver tissue. Further, GLUT2 and GLUT4 expressions were studied in three independent chronic liver disease cohorts. Signalling impairment distal to Akt in phosphorylation of AS160 and FoxO1 was evident in senescent HepG2 cells. Persistent nuclear localisation of FoxO1 was demonstrated in senescent cells despite insulin stimulation. Increased GLUT4 and decreased GLUT2 expressions were evident in senescent cells, human cirrhotic liver tissue and publically available liver disease datasets. Changes in GLUT expressions were associated with a poor clinical prognosis. In conclusion, selective insulin resistance is evident in senescent HepG2 cells and changes in GLUT expressions can be used as surrogate markers of hepatocyte senescence. - Highlights: • Senescent hepatocytes demonstrate selective insulin resistance. • GLUT changes act as markers of hepatocyte senescence and have prognostic value. • Study offers insight into long noticed intimacy of cirrhosis and insulin resistance.
Kelleher, R S; Murray, E F; Peterson, S W
The effect of incubation with insulin on insulin-receptor internalization by erythrocyte ghosts was investigated. The number of surface insulin receptors decreased by 30-40% after incubation of ghosts with insulin. Total insulin-receptor binding to solubilized ghosts was the same in insulin-incubated and control ghosts, whereas insulin binding to an internal vesicular fraction was substantially increased in insulin-incubated ghosts. Our findings suggest that erythrocyte-ghost insulin receptor...
Full Text Available The brain represents an important site for the action of insulin. Besides the traditionally known importance in glucoregulation, insulin has significant neurotrophic properties and influences the brain activity: insulin influences eating behavior, regulates the storage of energy and several aspects concerning memory and knowledge. Insulin resistance and hyperinsulinism could be associated with brain aging, vascular and metabolic pathologies. Elucidating the pathways and metabolism of brain insulin could have a major impact on future targeted therapies.
Full Text Available The purpose of the current research was to assess changes in daily insulin requirements in type 1 diabetic patients transitioning from multiple daily injections (MDI of insulin to continuous subcutaneous insulin infusion (CSII using an external insulin pump, according to clinical indications for changing therapy. The charts of 70 patients with type 1 diabetes (T1D initiating insulin pump therapy were retrospectively reviewed before CSII and after optimization of glycaemic profile with CSII during hospital admission. Daily insulin doses, basal/bolus distributions, dose changes during treatment transition and glycaemic outcomes with MDI and optimized CSII according to insulin pump indications were evaluated. Daily insulin doses were not significantly different among indication groups, with both MDI and CSII; likewise, the overall daily distribution of basal/rapid insulin ratio was similar, around 40/60. With optimized CSII, significant differences were found only in basal/bolus distribution in patients initiating CSII for recurrent hypoglycemia, who had a significantly lower basal (6.4% lower and a complementary higher bolus requirement, compared to patients initiating CSII for HbA1c ≥ 8.5%. At transition, basal insulin needs declined similarly in the high HbA1c and impractical/inflexible MDI groups by approximately 20%, and up to 30% in the recurrent hypoglycaemia group; bolus doses decreased by 20% when the indication was high HbA1c and by approximately 15% for the other indications. Glycaemic control was significantly improved only in patients initiating CSII for high HbA1c (≥8.5%. Insulin pump indication should be considered when starting T1D patients on CSII. These findings may support clinicians in decision making regarding insulin dose changes when initiating insulin pump therapy.
Abd El Aziz, Mirna S; Kahle, Melanie; Meier, Juris J; Nauck, Michael A
To study differences in clinical outcomes between initiating glucagon-like peptide-1 receptor agonist (GLP-1 RAs) vs insulin treatment in patients with type 2 diabetes treated with oral glucose-lowering medications (OGLM). Prospective, randomized trials comparing GLP-1 RA and insulin treatment head-to-head as add-on to OGLM were identified (PubMed). Differences from baseline values were compared for HbA1c, fasting plasma glucose, bodyweight, blood pressure, heartrate and lipoproteins. Proportions of patients reporting hypoglycaemic episodes were compared. Of 712 publications identified, 23 describing 19 clinical trials were included in the meta-analysis. Compared to insulin, GLP-1 RAs reduced HbA1c more effectively (Δ -.12%, P insulin was more effective in reducing fasting plasma glucose (Δ -1.8 mmol/L, P insulin treatment, with added benefits regarding bodyweight, hypoglycaemia, blood pressure and lipoproteins. These differences are in contrast to the fact that insulin is prescribed far more often than GLP-1 RAs. © 2016 John Wiley & Sons Ltd.
Liu, Yan; Chen, Xue Lian; Wang, Lei; Martins-Green, Manuela
Sustained increase in microvessel permeability results in cell and tissue damage. To date, it has not been possible to safely and specifically block increased microvessel permeability in vivo. We showed that insulin stimulates angiogenesis and that the new microvessels are associated with more αSMA-producing cells, suggesting greater stability. In this study, we show that local injection of insulin under the skin of mice significantly inhibits thrombin-induced microvessel permeability and that insulin improves the barrier function of primary human endothelial cells under conditions that mimic endothelium in vivo. These findings indicate that insulin antagonizes thrombin-induced microvessel permeability. At the cell and molecular levels, we show that insulin interferes with thrombin-induced VE-cadherin signaling by decreasing the ability of thrombin to induce VE-cadherin translocation to the cytoskeleton/nuclear compartment, leading to microvessel leakage. Simultaneously, the rapid activation of Src by insulin followed by the activation of Rac1, a small GTPase involved in cytoskeletal reorganization, leads to the maintenance of endothelial barrier, short-circuiting the slower thrombin-induced Src-RhoA signaling that leads to endothelial permeability. This novel mechanism by which insulin inhibits thrombin-induced permeability provides support for the use of insulin treatment in pathological conditions that involve blood-barrier dysfunction, especially as resuscitation treatment methods for extensive burns, sepsis, and other severe pathological conditions. © 2017 S. Karger AG, Basel.
Lawrence, James B.; Oxvig, Claus; Overgaard, Michael T.; Sottrup-Jensen, Lars; Gleich, Gerald J.; Hays, Lara G.; Yates, John R.; Conover, Cheryl A.
Proteolytic cleavage of the six known insulin-like growth factor binding proteins (IGFBPs) is a powerful means of rapid structure and function modification of these important growth-regulatory proteins. Intact IGFBP-4 is a potent inhibitor of IGF action in vitro, and cleavage of IGFBP-4 has been shown to abolish its ability to inhibit IGF stimulatory effects in a variety of systems, suggesting that IGFBP-4 proteolysis acts as a positive regulator of IGF bioavailability. Here we report the iso...
Durvasula, Kiranmai; Thulé, Peter M; Sambanis, Athanassios
One of the most promising cell-based therapies for combating insulin-dependent diabetes entails the use of genetically engineered non-β cells that secrete insulin in response to physiologic stimuli. A normal pancreatic β cell secretes insulin in a biphasic manner in response to glucose. The first phase is characterized by a transient stimulation of insulin to rapidly lower the blood glucose levels, which is followed by a second phase of insulin secretion to sustain the lowered blood glucose levels over a longer period of time. Previous studies have demonstrated hepatic and enteroendocrine cells to be appropriate hosts for recombinant insulin expression. Due to different insulin secretion kinetics from these cells, we hypothesized that a combination of the two cell types would mimic the biphasic insulin secretion of normal β cells with higher fidelity than either cell type alone. In this study, insulin secretion experiments were conducted with two hepatic cell lines (HepG2 and H4IIE) transduced with 1 of 3 adenoviruses expressing the insulin transgene and with a stably transfected recombinant intestinal cell line (GLUTag-INS). Insulin secretion was stimulated by exposing the cells to glucose only (hepatic cells), meat hydrolysate only (GLUTag-INS), or to a cocktail of the two secretagogues. It was found experimentally that the recombinant hepatic cells secreted insulin in a more sustained manner, whereas the recombinant intestinal cell line exhibited rapid insulin secretion kinetics upon stimulation. The insulin secretion profiles were computationally combined at different cell ratios to arrive at the combinatorial kinetics. Results indicate that combinations of these two cell types allow for tuning the first and second phase of insulin secretion better than either cell type alone. This work provides the basic framework in understanding the secretion kinetics of the combined system and advances it towards preclinical studies. Copyright © 2011 Wiley Periodicals
D. U. Campos-Delgado
Full Text Available A self-tuning algorithm is presented for on-line insulin dosage adjustment in type 1 diabetic patients (chronic stage. The algorithm suggested does not need information of the patient insulin–glucose dynamics (model-free. Three doses are programmed daily, where a combination of two types of insulin: rapid/short and intermediate/long acting is injected into the patient through a subcutaneous route. The doses adaptation is performed by reducing the error in the blood glucose level from euglycemics. In this way, a total of five doses are tuned per day: three rapid/short and two intermediate/long, where there is large penalty to avoid hypoglycemic scenarios. Closed-loop simulation results are illustrated using a detailed nonlinear model of the subcutaneous insulin–glucose dynamics in a type 1 diabetic patient with meal intake.
Dongerkery, Sahana Pai; Schroeder, Pamela R; Shomali, Mansur E
In this article, we examine the nature of the complex relationship between insulin and cardiovascular disease. With metabolic abnormalities comes increased risk for cardiovascular complications. We discuss the key factors implicated in development and progression of cardiovascular disease, its relationship to insulin therapy, and what can be learned from large, recent cardiovascular outcome studies. Preclinical studies suggest that insulin has positive effects of facilitating glucose entry into cells and maintaining euglycemia and negative effects of favoring obesity and atherogenesis under certain conditions. Confounding this relationship is that cardiovascular morbidity is linked closely to duration and control of diabetes, and insulin is often used in patients with diabetes of longer duration. However, more recent clinical studies examining the cardiovascular safety of insulin therapy have been reassuring. Diabetes and cardiovascular outcomes are closely linked. Many studies have implicated insulin resistance and hyperinsulinemia as a major factor for poor cardiovascular outcomes. Additional studies link the anabolic effects of therapeutic insulin to weight gain, along with hypoglycemia, which may further aggravate cardiovascular risk in this population. Though good glycemic control has been shown to improve microvascular risks in type 1 and type 2 diabetes, what are the known cardiovascular effects of insulin therapy? The ORIGIN trial suggests at least a neutral effect of the basal insulin glargine on cardiovascular outcomes. Recent studies have demonstrated that ultra-long-acting insulin analogs like insulin degludec are non-inferior to insulin glargine with regard to cardiovascular outcomes.
Tanti, J F; Gual, P; Grémeaux, T
Insulin resistance, when combined with impaired insulin secretion, contributes to the development of type 2 diabetes. Insulin resistance is characterised by a decrease in insulin effect on glucose transport in muscle and adipose tIssue. Tyrosine phosphorylation of insulin receptor substrate 1 (IRS......-1) and its binding to phosphatidylinositol 3-kinase (PI 3-kinase) are critical events in the insulin signalling cascade leading to insulin-stimulated glucose transport. Modification of IRS-1 by serine phosphorylation could be one of the mechanisms leading to a decrease in IRS-1 tyrosine...... to phosphorylate these serine residues have been identified. These exciting results suggest that serine phosphorylation of IRS-1 is a possible hallmark of insulin resistance in biologically insulin responsive cells or tIssues. Identifying the pathways by which "diabetogenic" factors activate IRS-1 kinases...
Ochman, Alexander R; Lipinski, Christopher A; Handler, Jeffrey A; Reaume, Andrew G; Saporito, Michael S
... (J Pharmacol Exp Ther 342:15-22, 2012). The current studies were designed to define the role of insulin in MLR-1023-mediated blood glucose lowering, to evaluate it in animal models of type 2 diabetes, and to compare it to the...
Burgdorf, Jeffrey; Colechio, Elizabeth M; Ghoreishi-Haack, Nayereh; Gross, Amanda L; Rex, Christopher S; Zhang, Xiao-Lei; Stanton, Patric K; Kroes, Roger A; Moskal, Joseph R
Posttraumatic stress disorder is an anxiety disorder characterized by deficits in the extinction of aversive memories. Insulin-like growth factor 1 (IGF1) is the only growth factor that has shown anxiolytic and antidepressant properties in human clinical trials. In animal studies, insulin-like growth factor binding protein 2 (IGFBP2) shows both IGF1-dependent and IGF1-independent pharmacological effects, and IGFBP2 expression is upregulated by rough-and-tumble play that induces resilience to stress. IGFBP2 was evaluated in Porsolt, contextual fear conditioning, and chronic unpredictable stress models of posttraumatic stress disorder. The dependence of IGFBP2 effects on IGF1- and AMPA-receptor activation was tested using selective receptor antagonists. Dendritic spine morphology was measured in the dentate gyrus and the medial prefrontal cortex 24 hours after in vivo dosing. IGFBP2 was 100 times more potent than IGF1 in the Porsolt test. Unlike IGF1, effects of IGFBP2 were not blocked by the IGF1-receptor antagonist JB1, or by the AMPA-receptor antagonist 2,3-Dioxo-6-nitro-1,2,3,4 tetrahydrobenzo[f]quinoxaline-7-sulfonamide (NBQX) in the Porsolt test. IGFBP2 (1 µg/kg) and IGF1 (100 µg/kg i.v.) each facilitated contextual fear extinction and consolidation. Using a chronic unpredictable stress paradigm, IGFBP2 reversed stress-induced effects in the Porsolt, novelty-induced hypophagia, sucrose preference, and ultrasonic vocalization assays. IGFBP2 also increased mature dendritic spine densities in the medial prefrontal cortex and hippocampus 24 hours postdosing. These data suggest that IGFBP2 has therapeutic-like effects in multiple rat models of posttraumatic stress disorder via a novel IGF1 receptor-independent mechanism. These data also suggest that the long-lasting effects of IGFBP2 may be due to facilitation of structural plasticity at the dendritic spine level. IGFBP2 and mimetics may have therapeutic potential for the treatment of posttraumatic stress disorder.
Colechio, Elizabeth M.; Ghoreishi-Haack, Nayereh; Gross, Amanda L.; Rex, Christopher S.; Zhang, Xiao-lei; Stanton, Patric K.; Kroes, Roger A.; Moskal, Joseph R.
Abstract Background: Posttraumatic stress disorder is an anxiety disorder characterized by deficits in the extinction of aversive memories. Insulin-like growth factor 1 (IGF1) is the only growth factor that has shown anxiolytic and antidepressant properties in human clinical trials. In animal studies, insulin-like growth factor binding protein 2 (IGFBP2) shows both IGF1-dependent and IGF1-independent pharmacological effects, and IGFBP2 expression is upregulated by rough-and-tumble play that induces resilience to stress. Methods: IGFBP2 was evaluated in Porsolt, contextual fear conditioning, and chronic unpredictable stress models of posttraumatic stress disorder. The dependence of IGFBP2 effects on IGF1- and AMPA-receptor activation was tested using selective receptor antagonists. Dendritic spine morphology was measured in the dentate gyrus and the medial prefrontal cortex 24 hours after in vivo dosing. Results: IGFBP2 was 100 times more potent than IGF1 in the Porsolt test. Unlike IGF1, effects of IGFBP2 were not blocked by the IGF1-receptor antagonist JB1, or by the AMPA-receptor antagonist 2,3-Dioxo-6-nitro-1,2,3,4 tetrahydrobenzo[f]quinoxaline-7-sulfonamide (NBQX) in the Porsolt test. IGFBP2 (1 µg/kg) and IGF1 (100 µg/kg i.v.) each facilitated contextual fear extinction and consolidation. Using a chronic unpredictable stress paradigm, IGFBP2 reversed stress-induced effects in the Porsolt, novelty-induced hypophagia, sucrose preference, and ultrasonic vocalization assays. IGFBP2 also increased mature dendritic spine densities in the medial prefrontal cortex and hippocampus 24 hours postdosing. Conclusions: These data suggest that IGFBP2 has therapeutic-like effects in multiple rat models of posttraumatic stress disorder via a novel IGF1 receptor-independent mechanism. These data also suggest that the long-lasting effects of IGFBP2 may be due to facilitation of structural plasticity at the dendritic spine level. IGFBP2 and mimetics may have therapeutic
Ross, Steven; Scoutaris, Nicolaos; Lamprou, Dimitrios; Mallinson, David; Douroumis, Dennis
Inkjet printing technology was used to apply insulin polymeric layers on metal microneedles for transdermal delivery. A range of various polymers such as gelatin (GLN), polyvinyl caprolactame-polyvinyl acetate-polyethylene glycol (SOL), poly(2-ethyl-2-oxazoline) (POX) and trehalose (THL) were assessed for their capacity to form thin uniform and homogeneous layers that preserve insulin intact. Atomic force microscopy (AFM) showed homogeneous insulin-polymer layers without any phase separation while SOL demonstrated the best performance. Circular discroism (CD) analysis of rehydrated films showed that insulin's alpha helices and β-sheet were well preserved for THL and SOL. In contrast, GLN and POX insulin layers revealed small band shifts indicating possible conformational changes. Insulin release in Franz diffusion cells from MNs inserted into porcine skin showed rapid release rates for POX and GLN within the first 20 min. Inkjet printing was proved an effective approach for transdermal delivery of insulin in solid state.
Full Text Available Kjeld Hermansen, Lene Sundahl Mortensen, Marie-Louise HermansenDepartment of Endocrinology and Metabolism C, Aarhus University Hospital, DK-8000 Aarhus, DenmarkAbstract: Patients with type 2 diabetes mellitus (T2DM have an increased risk of cardiovascular disease (CVD. Unfortunately, several potential barriers exist for CVD risk management in diabetes, including the need for significant lifestyle changes, potential problems with hypoglycemia, weight gain, injection tolerability, treatment complexity with current diabetes therapies and other, unmodifiable factors. Improving glycemic control may impact CVD risk. Treatment of T2DM usually starts with lifestyle changes such as diet and exercise. When these become insufficient, pharmacotherapy is required. Various oral antidiabetic drugs (OADs are available that reduce hyperglycemia. The first line of therapy is usually metformin, since it does not increase weight and seems to have a beneficial effect on CVD mortality and risk factors. As T2DM progresses, insulin treatment becomes necessary for the majority of patients. The last few years have seen the development of long-acting, rapid-acting, and premixed insulin analog formulations. The treat-to-target algorithms of recent studies combining OADs plus insulin analogs have demonstrated that patients can reach glycemic treatment targets with low risk of hypoglycemia, greater convenience, and – with some analogs – limited weight gain vs conventional insulins. These factors may possibly have a positive influence on CVD risk. Future studies will hopefully elucidate the benefits of this approach.Keywords: diabetes mellitus, type 2 diabetes, cardiovascular disease, hyperglycemia, insulin, oral antidiabetic drugs
Luiz Henrique Guerreiro
Full Text Available ABSTRACT Sustained release systems for therapeutic proteins have been widely studied targeting to improve the action of these drugs. Molecular entrapping of proteins is particularly challenging due to their conformational instability. We have developed a micro-structured poly-epsilon-caprolactone (PCL particle system loaded with human insulin using a simple double-emulsion w/o/w method followed by solvent evaporation method. This formulation is comprised by spheric-shaped microparticles with average size of 10 micrometers. In vitro release showed a biphasic behavior such as a rapid release with about 50% of drug delivered within 2 hours and a sustained phase for up to 48 h. The subcutaneous administration of microencapsulated insulin showed a biphasic effect on glycemia in streptozotocin-induced diabetic mice, compatible with short and intermediate-acting behaviors, with first transition peak at about 2 h and the second phase exerting effect for up to 48h after s.c. administration. This study reveals that a simplified double-emulsion system results in biocompatible human-insulin-loaded PCL microparticles that might be used for further development of optimized sustained release formulations of insulin to be used in the restoration of hormonal levels.
Mustafa Kemal Balcı
Full Text Available An increase in triglyceride levels in familial hyperlipidemia during pregnancy has been reported. Severe hypertriglyceridemia can lead to complications such as acute pancreatitis, preeclampsia, maternal and fetal complications. Because of the teratogenic effects associated with fibrate therapy in pregnancy, alternative treatment strategies such as insulin as a rapid and potent activator of lipoprotein lipase are required during pregnancy. We report a case of hypertriglyceridemia in a 33-year-old pregnant woman in whom treatment with merely single one time administration of Neutral Protamine Hagedorn insulin was accompanied by a reduction in the serum triglyceride level; to the best of our knowledge, this has never been reported in the literature. Her triglyceride level was 3616 mg/dL before insulin treatment and 1246 mg/dL after insulin treatment. Although this regimen was used safely and effectively in our patient, comprehensive studies are required to evaluate the effectiveness and safety of subcutaneously intermediate-acting Neutral Protamine Hagedorn insulin for the treatment of severe hypertriglyceridemia in non-diabetic pregnant women.
... page: https://medlineplus.gov/news/fullstory_165701.html Suicide by Insulin? Self-harm and suicidal behavior may ... higher rates of depression, the researchers explained. And suicide or suicide attempts using insulin or other diabetes ...
... this page: //medlineplus.gov/ency/article/003701.htm Insulin C-peptide test To use the sharing features ... a product that is created when the hormone insulin is produced and released into the body. The ...
The catheter at the end of the insulin pump is inserted through a needle into the abdominal ... with diabetes. Dosage instructions are entered into the pump's small computer and the appropriate amount of insulin ...
Neu, A; Lange, K; Barrett, T
defined. The proposed new classification for insulin management will be comprehensive, simple, and catchy. Currently available terms were included. This classification may offer the opportunity to compare therapeutic strategies without the currently existing confusion on the insulin regimen....
Maassen, J.A.; Burgering, B.M.T.; Medema, R.H.; Osterop, A.P.R.M.; Zon, G.C.M. van der; Möller, W.; Bos, J.L.
Ras-proteins are guanine nucleotide binding proteins, which, in the GTP bound state emit a strong mitogenic signal. In the GDP bound state, the protein appears inactive. We have found that stimulation by insulin of cells expressing elevated levels of insulin receptors results in a rapid conversion
Frøisland, Dag Helge; Graue, Marit; Markestad, Trond; Skrivarhaug, Torild; Wentzel-Larsen, Tore; Dahl-Jørgensen, Knut
To examine health-related quality of life (HRQOL) in children and adolescents with type 1 diabetes on intensive insulin treatment. All children and adolescents with type 1 diabetes above 8 years of age scheduled for follow-up at 21 paediatric departments in Norway, and one of their parents was invited to describe HRQOL by completing DISABKIDS questionnaires. HRQOL was related to sociodemographic factors (i.e. parental economy, education, marital status and to level of physical activity and disease characteristics, obtained from the Norwegian Childhood Diabetes Registry). Nine hundred and thirty seven (48%) and one of their parents responded. Mean duration of diabetes was 4.9 years (SD 3.3), 51% were girls, 56% used insulin pumps, and 44% used multiple insulin injections, predominantly of long-acting and rapid insulin analogues. Mean HbA1c was 8.5% (SD 1.3). Lower HRQOL scores were significantly associated with higher HbA1c, being a girl and experience of diabetes ketoacidosis. Mothers scored lower than fathers on total score and most subscales. No significant differences in scores were found between users of an insulin pump and multi-injection treatment. Health-related quality of life was related to metabolic control and gender, but not to mode of intensified insulin treatment. ©2013 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.
Vähätalo, Markku A.; Viikari, Jorma; Rönnemaa, Tapani
Our aim was to compare the effects of an intermediate acting human insulin (NPH) and a long-acting insulin analog, insulin glargine, in insulin naïve type 2 diabetes patients, stratified by the type of hyperglycemia (fasting or postprandial type). Based on different action profiles, we hypothesized that patients having different hyperglycemia types would react differently when treated with these insulins. This is a post hoc analysis of the Lanmet study data. The Lanmet study was a randomized,...
...) DRUGS: GENERAL GENERAL General Provisions § 200.15 Definition of term “insulin.” For purposes of sections 801 and 802 of the act and this title, the term insulin means the active principle of the pancreas... the same as, or similar to, naturally occurring insulins in structure, use, and intended effect and...
Pilz, Stefan; Rutters, Femke; Nijpels, Giel
OBJECTIVE: Accumulating evidence suggests an association between insulin sensitivity and albuminuria, which, even in the normal range, is a risk factor for cardiovascular diseases. We evaluated whether insulin sensitivity is associated with albuminuria in healthy subjects. RESEARCH DESIGN...... albuminuria. This finding suggests that reduced insulin sensitivity either is simply related to or might causally contribute to the initial pathogenesis of albuminuria....
Braak, Sebastiaan Johannes ter
There is epidemiological evidence that the use of some insulin analogues by diabetic patients is correlated with an increased cancer risk. In vitro exposure experiments revealed that insulin glargine (LANTUS) was the only commercial insulin analogue with an increased mitogenic potential. In the
Langeveld, Mirjam; Aerts, Johannes M. F. G.
Obesity is associated with an increased risk for insulin resistance, a state characterized by impaired responsiveness of liver, muscle and adipose tissue to insulin. One class of lipids involved in the development of insulin resistance are the (glyco)sphingolipids. Ceramide, the most simple
Cramer, J A; Okikawa, J; Bellaire, S; Clauson, P
The AERx Insulin Diabetes Management System [AERx iDMS, jointly developed by Novo Nordisk (Bagsvaerd, Denmark) and Aradigm Corp. (Hayward, CA)] provides insulin by pulmonary administration. This investigation was designed as a pilot trial to demonstrate the ability of patients to use the electronic device to deliver mealtime inhaled insulin doses and explore the impact on compliance. AERx iDMS was evaluated in a substudy of a 12-week, multicenter open trial by adult patients with type 2 diabetes previously on any insulin regimen. The device was used for dosing fast-acting human insulin immediately before main meals, in combination with bedtime NPH insulin. The AERx iDMS device recorded the date and time of each insulin inhalation, insulin units used, and inhalation technique during aerosol delivery. Compliance was defined as the percentage of prescribed doses taken during the treatment period, dose timing, and the efficiency of dosing technique. Insulin dosing for 49 patients (age 59.1 +/- 7.7 years) using AERx iDMS was monitored for 78.9 +/- 10 days (range, 41-94 days) with 226 +/- 35 doses (range, 122-272 doses). Patients inhaled on average 2.9 +/- 0.3 doses of insulin daily, taking an average of 11.8 +/- 5.6 units per dose. Compliance with the prescribed regimen was 94.3 +/- 9.1% (range, 45-100%). Overall, 4.2 +/- 9.5% of prescribed doses were omitted. Hemoglobin A1c decreased 0.77 +/- 0.96% from baseline to the end of the study. Inhalation technique was excellent, with 97% of patients experiencing fewer than five inadequate doses. Excellent compliance with AERx iDMS dosing, timing, and inhalation technique showed that the device was well accepted by patients. The electronic monitoring feature could be used as an educational tool to help patients and clinicians manage insulin dosing.
Coan, Kathryn E.; Schlinkert, Andrew B.; Beck, Brandon R.; Haakinson, Danielle J.; Castro, Janna C.; Apsey, Heidi A.; Schlinkert,, Richard T.; Cook, Curtiss B.
Objective Our objective was to assess the application of insulin regimens in surgical postoperative patients with diabetes. Methods A chart review was conducted of patients with diabetes who were hospitalized postoperatively between January 1 and April 30, 2011. Analysis was restricted to patients hospitalized for ≥3 days and excluded cases with an endocrinology consult. Insulin regimens were categorized as “basal plus short acting,” “short acting only,” or “none,” and the pattern of use was evaluated by hyperglycemia severity according to tertiles of both mean glucose and the number of glucose measurements >180 mg/dl. Results Among cases selected for analysis (n = 119), examination of changes in insulin use based on tertiles of mean glucose showed that use of basal plus short-acting insulin increased from 10% in the lowest tertile (mean glucose, 120 mg/dl) to 18% in the highest tertile (mean glucose, 198 mg/dl; p insulin only, with 12% receiving no insulin. Intensification of insulin to a basal plus short-acting regimen was also seen when changes were evaluated by the number of measurements >180 mg/dl (p insulin or received no insulin, respectively. Conclusions Use of basal plus short-acting insulin therapy increased with worsening hyperglycemia, but many cases did not have therapy intensified to the recommended insulin regimen—evidence of clinical inertia. Strategies should be devised to overcome inpatient clinical inertia in the treatment of postoperative patients with diabetes. PMID:23911169
Paula I. Moreira
Full Text Available Insulin, besides its glucose lowering effects, is involved in the modulation of lifespan, aging and memory and learning processes. As the population ages, neurodegenerative disorders become epidemic and a connection between insulin signaling dysregulation, cognitive decline and dementia has been established. Mitochondria are intracellular organelles that despite playing a critical role in cellular metabolism are also one of the major sources of reactive oxygen species. Mitochondrial dysfunction, oxidative stress and neuroinflammation, hallmarks of neurodegeneration, can result from impaired insulin signaling. Insulin-sensitizing drugs such as the thiazolidinediones are a new class of synthetic compounds that potentiate insulin action in the target tissues and act as specific agonists of the peroxisome proliferator-activated receptor gamma (PPAR-γ. Recently, several PPAR agonists have been proposed as novel and possible therapeutic agents for neurodegenerative disorders. Indeed, the literature shows that these agents are able to protect against mitochondrial dysfunction, oxidative damage, inflammation and apoptosis. This review discusses the role of mitochondria and insulin signaling in normal brain function and in neurodegeneration. Furthermore, the potential protective role of insulin and insulin sensitizers in Alzheimer´s, Parkinson´s and Huntington´s diseases and amyotrophic lateral sclerosis will be also discussed.
Yasujima, Tomoya; Saito, Kosuke; Moore, Rick; Negishi, Masahiko
Phenobarbital (PB) antagonized insulin to inactivate the insulin receptor and attenuated the insulin receptor downstream protein kinase B (AKT)-forkhead box protein O1 and extracellular signal-regulated kinase 1/2 signals in mouse primary hepatocytes and HepG2 cells. Hepatic AKT began dephosphorylation in an early stage of PB treatment, and blood glucose levels transiently increased in both wild-type and constitutive androstane receptor (CAR) knockout (KO) mice. On the other hand, blood glucose levels increased in wild-type mice, but not KO mice, in later stages of PB treatment. As a result, PB, acting as an insulin receptor antagonist, elicited CAR-independent increases and CAR-dependent decreases of blood glucose levels at these different stages of treatment, respectively. Reciprocally, insulin activation of the insulin receptor repressed CAR activation and induction of its target CYP2B6 gene in HepG2 cells. Thus, PB and insulin cross-talk through the insulin receptor to regulate glucose and drug metabolism reciprocally. Copyright © 2016 by U.S. Government work not protected by U.S. copyright.
HIS-388, a novel orally active and long-acting 11β-hydroxysteroid dehydrogenase type 1 inhibitor, ameliorates insulin sensitivity and glucose intolerance in diet-induced obesity and nongenetic type 2 diabetic murine models.
Okazaki, Seiji; Takahashi, Takehiro; Iwamura, Tomokatsu; Nakaki, Junko; Sekiya, Yumiko; Yagi, Mai; Kumagai, Hiroki; Sato, Mikiya; Sakami, Satoshi; Nitta, Aiko; Kawai, Koji; Kainoh, Mie
11β-Hydroxysteroid dehydrogenase type 1 (11β-HSD1) is considered a potential therapeutic target in the treatment of type 2 diabetes mellitus. In this study, we investigated the pharmacological properties of HIS-388 (N-[(1R,2s,3S,5s,7s)-5-hydroxyadamantan-2-yl]-3-(pyridin-2-yl) isoxazole-4-carboxamide), a newly synthesized 11β-HSD1 inhibitor, using several mouse models. In cortisone pellet-implanted mice in which hypercortisolism and hyperinsulinemia occur, single administration of HIS-388 exhibited potent and prolonged suppression of plasma cortisol and lowered plasma insulin levels. These effects were more potent than those achieved using the same dose of other 11β-HSD1 inhibitors (carbenoxolone and compound 544 [3-[(1s,3s)-adamantan-1-yl]-6,7,8,9-tetrahydro-5H-[1,2,4]triazolo[4,3-a]azepine]), indicating that HIS-388 potently and continuously suppresses 11β-HSD1 enzyme activity in vivo. In diet-induced obese mice, HIS-388 significantly decreased fasting blood glucose, plasma insulin concentration, and homeostasis model assessment-insulin resistance score, and ameliorated insulin sensitivity. In addition, HIS-388 significantly reduced body weight and suppressed the elevation of blood glucose during the pyruvate tolerance test. In nongenetic type 2 diabetic mice with disease induced by a high-fat diet and low-dose streptozotocin, HIS-388 also significantly decreased postprandial blood glucose and plasma insulin levels and improved glucose intolerance. The effects of HIS-388 on glucose metabolism were indistinguishable from those of an insulin sensitizer, pioglitazone. Our results suggest that HIS-388 is a potent agent against type 2 diabetes. Moreover, amelioration of diabetic symptoms by HIS-388 was at least in part attributable to an antiobesity effect or improvement of hepatic insulin resistance. Therefore, potent and long-lasting inhibition of 11β-HSD1 enzyme activity may be an effective approach for the treatment of type 2 diabetes and obesity
Full Text Available Vitamin D is characterized as a regulator of homeostasis of bone and mineral metabolism, but it can also provide nonskeletal actions because vitamin D receptors have been found in various tissues including the brain, prostate, breast, colon, pancreas, and immune cells. Bone metabolism, modulation of the immune response, and regulation of cell proliferation and differentiation are all biological functions of vitamin D. Vitamin D may play an important role in modifying the risk of cardiometabolic outcomes, including diabetes mellitus (DM, hypertension, and cardiovascular disease. The incidence of type 2 DM is increasing worldwide and results from a lack of insulin or inadequate insulin secretion following increases in insulin resistance. Therefore, it has been proposed that vitamin D deficiency plays an important role in insulin resistance resulting in diabetes. The potential role of vitamin D deficiency in insulin resistance has been proposed to be associated with inherited gene polymorphisms including vitamin D-binding protein, vitamin D receptor, and vitamin D 1alpha-hydroxylase gene. Other roles have been proposed to involve immunoregulatory function by activating innate and adaptive immunity and cytokine release, activating inflammation by upregulation of nuclear factor κB and inducing tumor necrosis factor α, and other molecular actions to maintain glucose homeostasis and mediate insulin sensitivity by a low calcium status, obesity, or by elevating serum levels of parathyroid hormone. These effects of vitamin D deficiency, either acting in concert or alone, all serve to increase insulin resistance. Although there is evidence to support a relationship between vitamin D status and insulin resistance, the underlying mechanism requires further exploration. The purpose of this paper was to review the current information available concerning the role of vitamin D in insulin resistance.
Medema, R.H.; Wubbolts, R.; Bos, J.L.
Insulin induces a rapid activation of p21ras in NIH 3T3 and Chinese hamster ovary cells that overexpress the insulin receptor. Previously, we suggested that p21ras may mediate insulin-induced gene expression. To test such a function of p21ras more directly, we studied the effect of different
Vigneri, R.; Gullo, D.; Pezzino, V.
The authors evaluated the effect of metformin (N,N-dimethylbiguanide), a biguanide known to be less toxic than phenformin, on insulin binding to its receptors, both in vitro and in vivo. Specific /sup 125/I-insulin binding to cultured IM-9 human lymphocytes and MCF-7 human breast cancer cells was determined after preincubation with metformin. Specific /sup 125/I-insulin binding to circulating monocytes was also evaluated in six controls, eight obese subjects, and six obese type II diabetic patients before and after a short-term treatment with metformin. Plasma insulin levels and blood glucose were also measured on both occasions. Metformin significantly increased insulin binding in vitro to both IM-9 lymphocytes and MCF-7 cells; the maximum increment was 47.1% and 38.0%, respectively. Metformin treatment significantly increased insulin binding in vivo to monocytes of obese subjects and diabetic patients. Scatchard analysis indicated that the increased binding was mainly due to an increase in receptor capacity. Insulin binding to monocytes of normal controls was unchanged after metformin as were insulin levels in all groups; blood glucose was significantly reduced after metformin only in diabetic patients. These data indicate that metformin increases insulin binding to its receptors in vitro and in vivo. The effect in vivo is observed in obese subjects and in obese type II diabetic patients, paralleling the clinical effectiveness of this antidiabetic agent, and is not due to receptor regulation by circulating insulin, since no variation in insulin levels was recorded.
Witek, Joanna; Witek, Przemysław; Pańkowska, Ewa
Insulin resistance is characterized by decreased tissue sensitivity to insulin. The hallmark of insulin resistance is decreased tissue glucose uptake despite normal or elevated insulin concentration. There has been an upward trend in the incidence of insulin resistance in developed countries, although in pediatric population it is difficult to assess. Both genetic and environmental factors play an important role in the etiology of insulin resistance, namely increased diet caloricity and decreased physical activity. Gradually, this leads to adipose tissue build-up. The role of visceral adipose tissue is of particular importance, mainly due to its significant endocrine activity, leading to adverse metabolic effects. The most important consequences of insulin resistance in children include increased incidence of type 2 diabetes, atherogenic dyslipidemia and arterial hypertension, which lead to increased cardiovascular risk. Children with insulin resistance can develop nonalcoholic steatohepatitis and sleep apnea syndrome. In case of female pediatric patients a higher incidence of polycystic ovary syndrome (PCOS) is observed. Furthermore, the authors reviewed opinions on risk factors for insulin resistance, as well as direct and indirect insulin resistance assessment methods. The article presents the principles of primary and secondary prevention of insulin resistance in children, with particular allowance for dietary recommendations and recommendations to increase physical activity, and, in selected cases, current guidelines on pharmacological treatment.
Banks, William A.; Owen, Joshua B.; Erickson, Michelle A
Insulin performs unique functions within the CNS. Produced nearly exclusively by the pancreas, insulin crosses the blood-brain barrier (BBB) using a saturable transporter, affecting feeding and cognition through CNS mechanisms largely independent of glucose utilization. Whereas peripheral insulin acts primarily as a metabolic regulatory hormone, CNS insulin has an array of effects on brain that may more closely resemble the actions of the ancestral insulin molecule. Brain endothelial cells (BEC), the cells that form the vascular BBB and contain the transporter that translocates insulin from blood to brain, is itself regulated by insulin. The insulin transporter is altered by physiological and pathological factors including hyperglycemia and the diabetic state. The latter can lead to BBB disruption. Pericytes, pluripotent cells in intimate contact with the BEC, protect the integrity of the BBB and its ability to transport insulin. Most of insulin’s known actions within the CNS are mediated through two canonical pathways, the phosphoinositide-3 kinase (PI3)/Akt and Ras/mitogen activated kinase (MAPK) cascades. Resistance to insulin action within the CNS, sometimes referred to as diabetes mellitus type III, is associated with peripheral insulin resistance, but it is possible that variable hormonal resistance syndromes exist so that resistance at one tissue bed may be independent of that at others. CNS insulin resistance is associated with Alzheimer’s disease, depression, and impaired baroreceptor gain in pregnancy. These aspects of CNS insulin action and the control of its entry by the BBB are likely only a small part of the story of insulin within the brain. PMID:22820012
Kleinridders, André; Ferris, Heather A.; Cai, Weikang
Insulin receptors, as well as IGF-1 receptors and their postreceptor signaling partners, are distributed throughout the brain. Insulin acts on these receptors to modulate peripheral metabolism, including regulation of appetite, reproductive function, body temperature, white fat mass, hepatic glucose output, and response to hypoglycemia. Insulin signaling also modulates neurotransmitter channel activity, brain cholesterol synthesis, and mitochondrial function. Disruption of insulin action in the brain leads to impairment of neuronal function and synaptogenesis. In addition, insulin signaling modulates phosphorylation of tau protein, an early component in the development of Alzheimer disease. Thus, alterations in insulin action in the brain can contribute to metabolic syndrome, and the development of mood disorders and neurodegenerative diseases. PMID:24931034
Vaag, Allan; Lund, Søren
This review addresses the apparent disconnect between international guideline recommendations, real-life clinical practice and the results of clinical trials, with regard to the initiation of insulin using basal (long-acting) or premixed insulin analogues in patients with type 2 diabetes (T2D...... and monitoring regimens. Enforced intensification of unrealistic complex treatment regimens and glycaemic targets may theoretically worsen the psychological well-being in some patients. More simple and sustainable treatment regimens and guidelines are urgently needed. As for the use of insulin in T2D......, there is limited evidence to convincingly support that initiation of insulin using basal insulin analogues is superior to initiation using premixed insulin analogues. While awaiting improved clinical efficacy and cost-effectiveness data, practical guidance from national and international diabetes organisations...
Full Text Available Insulin therapy is still the gold standard in diabetic pregnancy. Insulin lispro protamine suspension is an available basal insulin analogue. Aim. To study pregnancy outcomes of women with type 2 and gestational diabetes mellitus when insulin lispro protamine suspension or human NPH insulin was added to medical nutrition therapy and/or short-acting insulin. Methods. In this retrospective study, for maternal outcome we recorded time and mode of delivery, hypertension, glycaemic control (fasting blood glucose and HbA1c, hypoglycemias, weight increase, and insulin need. For neonatal outcome birth weight and weight class, congenital malformations was recorded and main neonatal complications. Two-tail Student's t-test and chi-square test were performed when applicable; significant P<0.05. Results. Eighty-nine pregnant women (25 with type 2 diabetes and 64 with gestational diabetes mellitus; 53 under insulin lispro protamine suspension and 36 under human NPH insulin were recruited. Maternal and neonatal outcomes were quite similar between the two therapeutic approaches; however, insulin need was higher in NPH. At the end of pregnancy, eight women with gestational diabetes continued to use only basal insulin analogue. Conclusions. Pregnancy outcome in type 2 and gestational diabetes mellitus with insulin lispro protamine suspension was similar to that with NPH insulin, except for a lower insulin requirement.
Full Text Available Jean-Christophe Philips, André ScheenDivision of Diabetes, Nutrition & Metabolic Disorders, Department of Medicine, CHU Sart-Tilman, University of Liège, Liège, Belgium Abstract: Insulin detemir is a soluble long-acting human insulin analogue at neutral pH with a unique mechanism of action. Following subcutaneous injection, insulin detemir binds to albumin via fatty acid chain, thereby providing slow absorption and a prolonged metabolic effect. Insulin detemir has a less variable pharmacokinetic profile than insulin suspension isophane or insulin ultralente. The use of insulin detemir can reduce the risk of hypoglycemia (especially nocturnal hypoglycemia in type 1 and type 2 diabetic patients. However, overall glycemic control, as assessed by glycated hemoglobin, is only marginally and not significantly improved compared with usual insulin therapy. The weight gain commonly associated with insulin therapy is rather limited when insulin detemir is used. In our experience, this new insulin analogue is preferably administrated at bedtime but can be proposed twice a day (in the morning and either before the dinner or at bedtime. Detemir is a promising option for basal insulin therapy in type 1 or type 2 diabetic patients.Keywords: diabetes mellitus, insulin detemir, hypoglycemia, insulin analogue, insulin therapy
Full Text Available The insulin classification regarding the duration of its effect gradually be-comes outdated; it is necessary to speak first about the insulin therapy regimes. The intensified insulin therapy regarding the type of multiple daily insulin injections be-comes an indisputable standard. The progress in the "protein engineering" with the formation of a wide spectrum of insulin analogues provides for moving forward to-wards modern diabetology and the concept of strict individualization of the insulin therapy. The experience becomes a pattern in creating two existing formulas of the insulin "short" analogues, namely HUMALAG with the replacement of the proline and lysinane places with those of 28 and 29, and NOVORAPID with aspartic acid at the 28th place in the B chain. The most recent long-effect analogues are created by amino acid changes with the glycine residual at the position A21 and two ariginines added to the positions B31 and B32 - insulin "glargin" - LANTUS. The development of short and long effect analogues imposed the logical need for formulating "new" fixed insulin combination's as well. New combination's are made of two kinds of ac-tual insulin, namely, the fast-effect analogues of the aspart type or lystroinsulin and protamine-retarded preparations - neutral protamine - lystroinsulin. Three kinds of combinations are made.
The prevalence of type 2 diabetes mellitus is rapidly rising worldwide, despite an increasing awareness of the problem. Hepatic insulin resistance is a key factor in the pathogenesis of type 2 diabetes. The liver is central to the maintenance of glucose homeostasis, but the role of intrinsic liver insulin signalling versus indirect effects on the regulation of hepatic metabolism remains under debate. Insulin receptor substrate-2 is a major signalling molecule downstream of the insulin recepto...
Full Text Available Aim. Inadequately controlled diabetes accounts for chronic complications and increases mortality. Its therapeutic management aims in normal HbA1C, prandial and postprandial glucose levels. This review discusses diabetes management focusing on the latest insulin analogues, alternative insulin delivery systems and the artificial pancreas. Results. Intensive insulin therapy with multiple daily injections (MDI allows better imitation of the physiological rhythm of insulin secretion. Longer-acting, basal insulin analogues provide concomitant improvements in safety, efficacy and variability of glycaemic control, followed by low risks of hypoglycaemia. Continuous subcutaneous insulin infusion (CSII provides long-term glycaemic control especially in type 1 diabetic patients, while reducing hypoglycaemic episodes and glycaemic variability. Continuous subcutaneous glucose monitoring (CGM systems provide information on postprandial glucose excursions and nocturnal hypo- and/or hyperglycemias. This information enhances treatment options, provides a useful tool for self-monitoring and allows safer achievement of treatment targets. In the absence of a cure-like pancreas or islets transplants, artificial “closed-loop” systems mimicking the pancreatic activity have been also developed. Conclusions. Individualized treatment plans for insulin initiation and administration mode are critical in achieving target glycaemic levels. Progress in these fields is expected to facilitate and improve the quality of life of diabetic patients.
Rasmussen, Christian Hove; Roge, Rikke Meldgaard; Ma, Zhulin
Background: Insulin aspart (IAsp) is used by many diabetics as a meal-time insulin to control postprandial glucose levels. As is the case with many other insulin types, the pharmacokinetics (PK), and consequently the pharmacodynamics (PD), is associated with clinical variability, both between...... to investigate and quantify the properties of the subcutaneous depot. Data from Brange et al. (1990) are used to determine the effects of insulin chemistry in subcutis on the absorption rate. Intravenous (i.v.) bolus and infusion PK data for human insulin are used to understand and quantify the systemic...... distribution and elimination (Porksen et al., 1997; Sjostrand et al., 2002). PK and PD profiles for type 1 diabetics from Chen et al. (2005) are analyzed to demonstrate the effects of IAsp antibodies in terms of bound and unbound insulin. PK profiles from Thorisdottir et al. (2009) and Ma et al. (2012b...
Richter, Erik; Galbo, H
The metabolic and hormonal adaptations to single exercise sessions and to exercise training in normal man and in patients with insulin-dependent as well as non-insulin-dependent diabetes mellitus are reviewed. In insulin-dependent (type I) diabetes good metabolic control is best obtained...... of the patient's reaction to exercise is desirable, which necessitates frequent self-monitoring of plasma glucose. It may often be necessary to diminish the insulin dose before exercise, and/or to ingest additional carbohydrate during or after exercise. In non-insulin-dependent (type II) diabetes, exercise...... by a regular pattern of life which will lead to a fairly constant demand for insulin from day to day. Exercise is by nature a perturbation that makes treatment of diabetes difficult: Muscle contractions per se tend to decrease the plasma glucose concentration whereas the exercise-induced response of the so...
Full Text Available This communication explores the concept of flexibility, a propos insulin preparations and insulin regimes used in the management of type 2 diabetes. The flexibility of an insulin regime or preparation is defined as their ability to be injected at variable times, with variable injection-meal time gaps, in a dose frequency and quantum determined by shared decision making, with a minimal requirement of glucose monitoring and health professional consultation, with no compromise on safety, efficiency and tolerability. The relative flexibility of various basal, prandial and dual action insulins, as well as intensive regimes, is compared. The biopsychosocial model of health is used to assess the utility of different insulins while encouraging a philosophy of flexible insulin usage.
Moira S. Lewitt
Full Text Available The insulin-like growth factor (IGF system, acting in concert with other hormone axes, is important in normal metabolism. In obesity, the hyperinsulinaemia that accompanies peripheral insulin resistance leads to reduced growth hormone (GH secretion, while total IGF-I levels are relatively unchanged due to increased hepatic GH sensitivity. IGF-binding protein (IGFBP-1 levels are suppressed in relation to the increase in insulin levels in obesity and low levels predict the development of type 2 diabetes several years later. Visceral adiposity and hepatic steatosis, along with a chronic inflammation, contribute to the IGF system phenotype in individuals with metabolic syndrome and type 2 diabetes mellitus, including changes in the normal inverse relationship between IGFBP-1 and insulin, with IGFBP-1 concentrations that are inappropriately normal or elevated. The IGF system is implicated in the vascular and other complications of these disorders and is therefore a potential therapeutic target.
T S Dzhavakhishvili
Full Text Available The aim of the present study was to investigate whether insulin treatment-induced weight gain had an adverse impact on cardiovascular risk factors in insulin-treated type 2 diabetic patients during the first year after initiating insulin therapy when insulin analogues or human insulins are used. A total of 157 patients with newly insulinized type 2 diabetes were included in the study. The patients were divided in two groups. First group consisted of subjects (mean age 57 [45; 73], duration of diabetes of 10 years [4; 16] who had received long-acting basal (glargine, detemir, premixed (biphasic insulin aspart 30, Humalog Mix 25 or short-acting (aspart, lispro insulin analogues. Patients from second group (mean age 59 [46; 75], duration of diabetes of 10 years [5; 15] were treated with intermediate-acting basal (Protophane, Humulin NPH insulin, premixed (biphasic human insulin 30, Humulin M3 and regular (Actrapid, Humulin R human insulins. Our study has shown that insulin-induced weight gain may not adversely affect cardiovascular risk factors, particularly, lipid profile, in insulin-treated type 2 diabetic patients during the first year after initiating insulin therapy. Use of insulin analogues for treatment of type 2 diabetes patients results in better glycaemic control, significant declines in blood lipid concentrations, less increase in waist circumference compared with human insulins during the first year after initiating insulin therapy.
Celeste C. Quianzon
Full Text Available The advancement of diabetes treatment has gone from crude extracts of insulin and accidental discovery of sulfa-like drugs in antibiotics to the development of drugs based on improved understanding of the pathophysiology of diabetes mellitus. This article will review the history of the discovery and development of insulin. A companion focusing on non-insulin diabetes agents will follow in the next issue of JCHIMP.
Semenkovich, Clay F.
Considerable evidence supports the association between insulin resistance and vascular disease, and this has led to wide acceptance of the clustering of hyperlipidemia, glucose intolerance, hypertension, and obesity as a clinical entity, the metabolic syndrome. While insulin resistance, by promoting dyslipidemia and other metabolic abnormalities, is part of the proatherogenic milieu, it is possible that insulin resistance itself in the vascular wall does not promote atherosclerosis. Recent fi...
Cholerton, Brenna; Baker, Laura D.; Craft, Suzanne
Cognitive disorders of aging represent a serious threat to the social and economic welfare of current society. It is now widely recognized that pathology related to such conditions, particularly Alzheimer’s disease, likely begins years or decades prior to the onset of clinical dementia symptoms. This revelation has led researchers to consider candidate mechanisms precipitating the cascade of neuropathological events that eventually lead to clinical Alzheimer’s disease. Insulin, a hormone with potent effects in the brain, has recently received a great deal of attention for its potential beneficial and protective role in cognitive function. Insulin resistance, which refers to the reduced sensitivity of target tissues to the favorable effects of insulin, is related to multiple chronic conditions known to impact cognition and increase dementia risk. With insulin resistance-associated conditions reaching epidemic proportions, the prevalence of Alzheimer’s disease and other cognitive disorders will continue to rise exponentially. Fortunately, these chronic insulin-related conditions are amenable to pharmacological intervention. As a result, novel therapeutic strategies that focus on increasing insulin sensitivity in the brain may be an important target for protecting or treating cognitive decline. The following review will highlight our current understanding of the role of insulin in brain, potential mechanisms underlying the link between insulin resistance and dementia, and current experimental therapeutic strategies aimed at improving cognitive function via modifying the brain’s insulin sensitivity. PMID:24070815
As type 2 diabetes mellitus progresses, most patients require treatment with basal insulin in combination with another agent to achieve recommended glycaemic targets. The purpose of this systematic review was to examine the evidence supporting the use of the available add-on treatments [rapid-acting insulin (RAI), glucagon-like peptide-1 receptor agonists (GLP-1 RAs), dipeptidyl peptidase (DPP)-4 inhibitors and sodium-glucose cotransporter-2 (SGLT-2) inhibitors] to basal insulin. MEDLINE, EMBASE and EBSCOhost were searched for English-language articles, and all those captured were original articles (case studies and narrative reviews were omitted). Data on study design, population demographics, interventions and outcomes were tabulated. The extracted outcome data included changes in glycated haemoglobin (HbA1c), fasting plasma glucose (FPG) and postprandial plasma glucose (PPG), as well as body weight and safety data. A total of 88 publications were deemed relevant. All treatments reduced HbA1c and FPG. The most pronounced reductions in PPG, an unmet need in patients not controlled by basal insulin, were seen following administration of RAIs and short-acting GLP-1 RAs, although data for this outcome are generally lacking. Body weight benefits were observed with GLP-1 RAs and SGLT-2 inhibitors. However, as only articles in English were included, the result was a possible publication bias, while the diversity of study designs and drug combinations limited comparisons between studies. The evidence supports effectiveness of the available add-on treatments to basal insulin. However, other factors, such as potential body-weight increases, convenience/compliance and adverse events, particularly hypoglycaemia, should be considered on a patient-by-patient basis to optimalize treatment outcomes. Copyright © 2016 Elsevier Masson SAS. All rights reserved.
Fischer, Emil; Almási, Attila; Bojcsev, Sztojan; Fischer, Tamás; Kovács, Noémi Piroska; Perjési, Pál
Luminal appearance of 4-nitrophenol (PNP) metabolites (4-nitrophenol-β-glucuronide (PNP-G) and 4-nitrophenol-sulfate (PNP-S)) and activity of the related metabolic enzymes have been investigated in control and experimental diabetic rats. Experimental diabetes was induced by administration of streptozotocin (65 mg/kg i.v.). PNP (500 μmol/L) was luminally perfused in the small intestine and the metabolites were determined in the perfusion solution. Effect of insulin replacement was also investigated in the diabetic rats. It was found that experimental diabetes increased the luminal appearance of PNP-G, which could be completely compensated by rapid-acting insulin administration (1 U/kg i.v.). Activities of the enzymes involved in PNP-G production (UDP-glucuronyltransferase and β-glucuronidase) were also elevated; however, these changes were only partially compensated by insulin. Luminal appearance of PNP-S was not significantly changed by administration of streptozotocin and insulin. Activities of the enzymes of PNP-S production (sulfotransferases and arylsulfatases) did not change in the diabetic rats. The results indicate that experimental diabetes can provoke changes in intestinal drug metabolism. It increased intestinal glucuronidation of PNP but did not influence sulfate conjugation. No direct correlation was found between the changes of metabolic enzyme activities and the luminal appearance of the metabolites.
Al-Mahmood, Abu Kholdun; Ismail, Aziz Al-Safi; Rashid, Faridah Abdul; Wan Bebakar, Wan Mohamad
Insulin insensitivity is a common finding in several metabolic disorders including glucose intolerance, dyslipidemia, hyperuricemia and hypertension. Most of the previous studies on insulin sensitivity were performed on diabetic or obese population. So our knowledge about insulin sensitivity of healthy population remains limited. Rising prevalence of obesity, diabetes and metabolic syndrome is a serious issue in Malaysia and some other rapidly developing countries. So it is important to look at the insulin sensitivity status of healthy Malaysian subjects and to compare it in future with those of diabetic, obese or metabolic syndrome patients. In this study we sampled subjects who were independent of confounding factors such as obesity (including abdominal obesity), hypertension and glucose intolerance (diabetes, IGT or IFG) which may influence insulin sensitivity. Fasting plasma glucose, fasting insulin and lipid profile were determined. Insulin sensitivity and secretory status were calculated using the homeostasis model assessment (HOMA) software (HOMA%S, HOMA%B and HOMA-IR). The insulin sensitivity (HOMA%S) of healthy Malay subjects aged between 30-60 years was 155.17%, HOMA-IR was 1.05 and HOMA%B was 116.65% (values adjusted for age, sex, BMI and waist circumference). It was seen that non-obese Malaysians can prevent age related lowering of insulin sensitivity if they can retain their BMI within limit.
Giddings, A E; Rowlands, B J; Mangnall, D; Clark, R G
Long-term hyperinsulinemia and improved glucose tolerance were produced postoperatively by intravenous feeding with glucose or sorbitol. Raised immuno-reactive insulin (IRI) values persisted eight hours after carbohydrate infusions although the basal plasma glucose concentrations had returned to control values. Plasma glucose curves were normal at this time but were associated with an increased IRI response. These findings suggest that insulin secretion is modified by glucose not only in the short term but also by a separate effect acting over many hours. The combination of starvation and low dose glucose infusion to simulate the hyperglycemia of operation also produced high IRI values but these were associated with a rapid fall in the plasma glucose curve. Starvation alone reduced basal values of plasma glucose and IRI, and the IRI response to glucose infusion was also reduced, despite the plasma glucose curve being at a higher level. It is suggested that the high values of IRI reported in the postoperative period are mediated by a long-term effect of the small but sustained rise in basal plasma glucose. This specific role of glucose in the long-term potentiation of insulin secretion make it the carbohydrate of choice for the intravenous feeding in postoperative patients. PMID:414664
Full Text Available Improved glycemic control with insulin pump therapy in patients with type 1 diabetes mellitus has shown gradual reductions in nephropathy and retinopathy. More recently, the emerging concept of the artificial pancreas, comprising an insulin pump coupled to a continuous glucose meter and a control algorithm, would become the next major breakthrough in diabetes care. The patient safety and the efficiency of the therapy are directly derived from the delivery accuracy of rapid-acting insulin. For this purpose, a specific precision-oriented design of micropump has been built. The device, made of a stack of three silicon wafers, comprises two check valves and a pumping membrane that is actuated against stop limiters by a piezo actuator. Two membranes comprising piezoresistive strain gauges have been implemented to measure the pressure in the pumping chamber and at the outlet of the pump. Their high sensitivity makes possible the monitoring of the pumping accuracy with a tolerance of ±5% for each individual stroke of 200 nL. The capability of these sensors to monitor priming, reservoir overpressure, reservoir emptying, outlet occlusion and valve leakage has also been studied.
Galan, B.E. de
There is ongoing interest in optimizing basal insulin treatment by developing insulins with a flat pharmacological profile, a long duration of action (typically beyond 24 hours) and minimum day-to-day variation. Glargine-300 is a modified form of the long-acting insulin analog glargine in that it
Von Hunolstein, Jean-Jacques; Nebigil, Canan G
Because of its increasing prevalence and morbi-mortality, obesity is a major health problem. Obesity etiology includes a combination of excess dietary calories and decreased physical activity, coupled with either predisposing genetic factors or metabolic disorders such as insulin resistance. Adipose tissue secretes several metabolically important proteins known as 'adipokines' that play a major role in obesity and insulin resistance. High levels of a newly identified group of adipokines, called prokineticins, have been found in obese adipose tissues. Prokineticins are peptide hormones released principally from macrophages and reproductive organs. They act on the G protein-coupled receptors PKR1 and PKR2. This review aims to provide an overview of current knowledge of the role of prokineticins and their receptors in the development of obesity and insulin resistance. The principal biological effect of prokineticins in the central nervous system is the control of food intake. Nevertheless, peripheral biological effects of prokineticin are associated with increasing insulin sensitivity and suppressing the adipose tissue expansion. We outline the biological significance of the central and peripheral effects of prokineticins, and the potential of their receptors as targets for the treatment of obesity and insulin resistance.
Since metformin became available for therapeutic utilisation, more than 30 years ago, it has been found that the compound was able to reduce hyperglycaemia in diabetic subjects without any stimulation of B cell secretion. The mechanism(s) of action of this drug has been better clarified these last 5-10 years even if all its aspects are not yet fully elucidated. What has been established, however, since the beginning of its clinical use, is that metformin can act in the presence of insulin in "facilitating" its effects. This had lead some authors to investigate the possible synergistic effect of metformin added to insulin therapy. Some studies have thus shown that insulin requirements were significantly decreased during the administration of biguanides, and effect which seemed to be maximal shortly after commencing the drug. Some authors have also claimed that biguanides smooth out blood glucose profiles in brittle diabetes, but this is denied by others. A decrease in insulin requirements may be of interest in diminishing peripheral hyperinsulinism and its possible consequences. It remains questionable whether the addition of metformin in the long term is to be recommended in Type 1 diabetic patients. However, such a clarification of decrease insulin requirements can help in the understanding of the clinical significance of metformin's actions in diabetes (impact on insulin resistance, receptor and post-receptor effects).
Jhon Jairo BejaranoRoncancio
Full Text Available Desde la década de los noventa han sido diseñados análogos de insulina para el manejo de pacientes diabéticos usando técnicas de ADN recombinante. Las modificaciones de la molécula original de insulina humana les confieren una rápida, ultrarrápida y prolongada acción. Entre las insulinas ultra rápidas están la Aspártica, la Lispro y la Glulisina y entre las de acción prolongada están la Glargina y la Detemir. También se encuentran mezcladas con insulina humana NPH en diferentes proporciones. Aunque existen diferentes tipos de algoritmos terapéuticos, la insulinización sigue siendo una terapia artesanal basada en la experiencia del especialista tratante. La introducción de los análogos de insulina hace más factible el empleo de bolos correctores o dosis extra de insulina para reducir las hipoglicemias puntuales en cualquier momento del día y facilitar el manejo de los carbohidratos en la dieta.Insulin analogues have been engineered through recombinant DNA techniques for managing diabetic patients since the 1990s; modifications to the original human insulin molecule have made them rapid, ultrarapid and prolonged acting. Aspart, lispro and glulisine are ultrafast insulins and glargine and detemir are longacting ones. Such insulins may be premixed in formulations combining neutral protamine Hagedorn (NPH with regular human insulin (70%/30%. Different types of therapeutic algorithms are available nowadays but insulinisation remains a crafted therapy based on the treating specialist's experience. The introduction of insulin analogues enables using correction boluses or extra doses of insulin to reduce hypoglycaemia at any time of the day and facilitates handling carbohydrates in a particular patient's diet.
Studies have shown that while injections of insulin cause an increase in fat mass, infusions of insulin increase fat mass. The aim of this paper was to test the hypothesis that if an increase in glycogen is an indicator of an impending increase in adipose mass, then insulin infusions should not increase glycogen, while insulin ...
Ramiya, V K; Maclaren, N K
Insulin-dependent diabetes (IDD) is a chronic immune-endocrine disease in which there is a progressive destruction of insulin-secreting pancreatic beta cells, caused primarily by autoreactive T cells. Many islet cell proteins including insulin, glutamic acid decarboxylase, and tyrosine phosphatase antigens (IA-2) are targeted by the autoimmune responses in IDD patients. Since its discovery 75 years ago, insulin has been the major player in the clinical management of hyperglycaemia in these patients. The morbidity and mortality associated with IDD derives mainly from the complications of the disease. However, routine insulin injections seldom achieve a consistent, near-normal glucose level, where multiple daily doses of the hormone involve considerable restrictions to a normal lifestyle. In terms of economics, the management of diabetes is expensive, and in the USA diabetes alone accounts for one seventh of the healthcare budget. These clinical, lifestyle and economic issues emphasize the need to investigate alternative preventative measures in IDD treatment. Recent reports suggest a pivotal role for insulin in various aspects of the immune system. In this study, insulin and B-chain were used to modulate autoimmune responses in non-obese diabetic mice, findings which have therapeutic implications in man.
Lin, Yi; Sun, Zhongjie
BACKGROUND AND PURPOSE The thyroid hormone, triiodothyronine (T3) has many metabolic functions. Unexpectedly, exogenous T3 lowered blood glucose in db/db mice, a model of type 2 diabetes. Here, we have explored this finding and its possible mechanisms further. EXPERIMENTAL APPROACH db/db and lean mice were treated with T3, the phosphoinositide 3- kinase (PI3-kinase) inhibitor, LY294002, plus T3, or vehicles. Blood glucose, insulin sensitivity, levels and synthesis were measured. Effects of T3 on intracellular insulin signaling were analyzed in 3T3-L1 pre-adipocytes with Western blotting. Knock-down of the thyroid hormone receptor α1 (TRα1) in 3T3-L1 cells was achieved with an appropriate silencing RNA (siRNA). KEY RESULTS Single injections of T3 (7 ng·g−1 i.p.) rapidly and markedly attenuated hyperglycemia. Treatment with T3 (14 ng·g−1·day−1, 18 days) dose-dependently attenuated blood glucose and increased insulin sensitivity in db/db mice. Higher doses of T3 (28 ng·g−1·day−1) reversed insulin resistance in db/db mice. T3 also increased insulin levels in plasma and the neurogenic differentiation factor (an insulin synthesis transcription factor) and insulin storage in pancreatic islets in db/db mice. These anti-diabetic effects of T3 were abolished by the PI3-kinase inhibitor (LY294002). In 3T3-L1 preadipocytes, T3 enhanced insulin-induced tyrosine phosphorylation of insulin receptor substrate (IRS)-1 and activation of PI3-kinase, effects blocked by siRNA for TRα1. CONCLUSIONS AND IMPLICATIONS T3 potentiated insulin signaling, improved insulin sensitivity, and increased insulin synthesis, which may contribute to its anti-diabetic effects. These findings may provide new approaches to the treatment of type 2 diabetes. PMID:20883475
studies in β cell-specific IR knockout mice, which develop peripheral insulin resistance and diabetes, most probably due to the changes in the pattern of insulin secretion (Kulkarni et al 1999). FFA also affects downstream insulin signalling molecules. It inhibits insulin activation of IRS-1-associated PI3K activity in muscle.
Sandoval, Darleen; Sisley, Stephanie R
Type 2 diabetes is often treated with a class of drugs referred to as glucagon-like peptide-1 (GLP-1) analogs. GLP-1 is a peptide secreted by the gut that acts through only one known receptor, the GLP-1 receptor. The primary function of GLP-1 is thought to be lowering of postprandial glucose levels. Indeed, medications utilizing this system, including the long-acting GLP-1 analogs liraglutide and exenatide, are beneficial in reducing both blood sugars and body weight. GLP-1 analogs were long presumed to affect glucose control through their ability to increase insulin levels through peripheral action on beta cells. However, multiple lines of data point to the ability of GLP-1 to act within the brain to alter glucose regulation. In this review we will discuss the evidence for a central GLP-1 system and the effects of GLP-1 in the brain on regulating multiple facets of glucose homeostasis including glucose tolerance, insulin production, insulin sensitivity, hepatic glucose production, muscle glucose uptake, and connections of the central GLP-1 system to the gut. Although the evidence indicates that GLP-1 receptors in the brain are not necessary for physiologic control of glucose regulation, we discuss the research showing a strong effect of acute manipulation of the central GLP-1 system on glucose control and how it is relevant to type 2 diabetic patients. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
Visser, S.T.; Vegter, S.; Boersma, C.; De Grooth, R.; Postma, M.J.
OBJECTIVES: Newer long-acting insulin analogs have shown to result in several treatment improvements if compared with NPH insulins. Promising results from clinical trials require confirmation from observational settings reflecting potential “real-life” benefits. Therefore, the current study aimed to
Vedtofte, Louise; Knop, Filip K; Vilsbøll, Tina
Insulin therapy in the management of Type 2 diabetes is often postponed and/or not adequately intensified to maintain glycemic control because of the risk of weight gain and hypoglycemia. A fixed combination of the long-acting insulin degludec and liraglutide has recently been accepted by the EMA...
Fukushima, Keizo; Yamazaki, Takenao; Hasegawa, Ryo; Ito, Yukako; Sugioka, Nobuyuki; Takada, Kanji
This study tested the hypothesis that dissolving microneedles are a useful transdermal drug delivery system (TDDS) for insulin. Insulin was loaded on a patch (1.0 cm2) that had 100 dissolving microneedles with chondroitin sulfate by microfabrication technology. Pharmacodynamic evaluation was performed by applying two or four patches to the shaved abdominal skin of dogs, and blood samples were collected for 360 min to measure plasma glucose and insulin levels. In diffusion experiment, microneedles containing fluorescein isothiocyanate-insulin and/or Evans blue were administered to the rat skin, and the diffusion rates of tracers were recorded. The mean length, diameter of basement, and drug-loaded space from the top of the microneedles were 492.6 +/- 2.4, 290.0 +/- 3.6, and 316.0 +/- 7.3 microm, respectively. The insulin content was 1.67 +/- 0.17 IU per patch. The time when the minimum plasma glucose level was obtained was 50.0 +/- 8.7 min for two-patch and 82.5 +/- 14.4 min for four-patch studies. A dose-dependent hypoglycemic effect was observed. By comparing the cumulative percentage change in the plasma glucose level between insulin microneedles and solution, the relative physiological availabilities were calculated to be 71.1 +/- 17.8% (for two patches) and 59.3 +/- 4.4% (for four patches). Bioavailabilities of insulin from microneedles were 72.1 +/- 11.6% (for two patches) and 72.4 +/- 8.3% (for four patches). High diffusion rates of fluorescein isothiocyanate-insulin and Evans blue were observed at the administered skin site and correlated well with the high absorption rate of insulin into the systemic circulation. Insulin was stable in dissolving microneedles for 1 month at 4 degrees C; the recovered percentage was 99.2 +/- 13.9%. Dissolving microneedles were demonstrated to be a useful TDDS as an immediate-acting insulin preparation.
Frøsig, Christian; Jensen, Thomas Elbenhardt; Jeppesen, Jacob
The 5'-AMP-activated protein kinase (AMPK) is considered "a metabolic master-switch" in skeletal muscle reducing ATP- consuming processes whilst stimulating ATP regeneration. Within recent years, AMPK has also been proposed as a potential target to attenuate insulin resistance, although the exact...... role of AMPK is not well understood. Here we hypothesized that mice lacking a2AMPK activity in muscle would be more susceptible to develop insulin resistance associated with ageing alone or in combination with high fat diet. Young (~4 month) or old (~18 month) wild type and muscle specific a2AMPK...... kinase-dead mice on chow diet as well as old mice on 17 weeks of high fat diet were studied for whole body glucose homeostasis (OGTT, ITT and HOMA-IR), insulin signaling and insulin-stimulated glucose uptake in muscle. We demonstrate that high fat diet in old mice results in impaired glucose homeostasis...
Kesten, Dov; Horovitz-Fried, Miriam; Brutman-Barazani, Tamar; Sampson, Sanford R
Insulin binding to its cell surface receptor (IR) activates a cascade of events leading to its biological effects. The Insulin-IR complex is rapidly internalized and then is either recycled back to the plasma membrane or sent to lysosomes for degradation. Although most of the receptor is recycled or degraded, a small amount may escape this pathway and migrate to the nucleus of the cell where it might be important in promulgation of receptor signals. In this study we explored the mechanism by which insulin induces IR translocation to the cell nucleus. Experiments were performed cultured L6 myoblasts, AML liver cells and 3T3-L1 adipocytes. Insulin treatment induced a rapid increase in nuclear IR protein levels within 2 to 5 min. Treatment with WGA, an inhibitor of nuclear import, reduced insulin-induced increases nuclear IR protein; IR was, however, translocated to a perinuclear location. Bioinformatics tools predicted a potential nuclear localization sequence (NLS) on IR. Immunofluorescence staining showed that a point mutation on the predicted NLS blocked insulin-induced IR nuclear translocation. In addition, blockade of nuclear IR activation in isolated nuclei by an IR blocking antibody abrogated insulin-induced increases in IR tyrosine phosphorylation and nuclear PKCδ levels. Furthermore, over expression of mutated IR reduced insulin-induced glucose uptake and PKB phosphorylation. When added to isolated nuclei, insulin induced IR phosphorylation but had no effect on nuclear IR protein levels. These results raise questions regarding the possible role of nuclear IR in IR signaling and insulin resistance. Copyright © 2018 Elsevier B.V. All rights reserved.
Ning, Jie; Hong, Tao; Yang, Xuefeng; Mei, Shuang; Liu, Zhenqi; Liu, Hui-Yu
The primary player that induces insulin resistance has not been established. Here, we studied whether or not fat can cause insulin resistance in the presence of insulin deficiency. Our results showed that high-fat diet (HFD) induced insulin resistance in C57BL/6 (B6) mice. The HFD-induced insulin resistance was prevented largely by the streptozotocin (STZ)-induced moderate insulin deficiency. The STZ-induced insulin deficiency prevented the HFD-induced ectopic fat accumulation and oxidative stress in liver and gastrocnemius. The STZ-induced insulin deficiency prevented the HFD- or insulin-induced increase in hepatic expression of long-chain acyl-CoA synthetases (ACSL), which are necessary for fatty acid activation. HFD increased mitochondrial contents of long-chain acyl-CoAs, whereas it decreased mitochondrial ADP/ATP ratio, and these HFD-induced changes were prevented by the STZ-induced insulin deficiency. In cultured hepatocytes, we observed that expressions of ACSL1 and -5 were stimulated by insulin signaling. Results in cultured cells also showed that blunting insulin signaling by the PI3K inhibitor LY-294002 prevented fat accumulation, oxidative stress, and insulin resistance induced by the prolonged exposure to either insulin or oleate plus sera that normally contain insulin. Finally, knockdown of the insulin receptor prevented the oxidative stress and insulin resistance induced by the prolonged exposure to insulin or oleate plus sera. Together, our results show that insulin and insulin signaling are required for fat induction of insulin resistance in mice and cultured mouse hepatocytes. PMID:21586696
Holst, Jens Juul; Holland, William; Gromada, Jesper
In August 2016, several leaders in glucagon biology gathered for the European Association for the Study of Diabetes Hagedorn Workshop in Oxford, England. A key point of discussion focused on the need for basal insulin to allow for the therapeutic benefit of glucagon blockade in the treatment...... of the discussion as a consensus was reached. Agents that antagonize glucagon may be of great benefit for the treatment of diabetes; however, sufficient levels of basal insulin are required for their therapeutic efficacy....
Sjøberg, Kim Anker
In this PhD work a new method for measuring microvascular recruitment was developed and evaluated, using continues real-time imaging of contrast enhanced ultrasound. Gas-filled microbubbles were infused intravenously and by taking advantage of the echogenic properties of the microbubbles the reso......In this PhD work a new method for measuring microvascular recruitment was developed and evaluated, using continues real-time imaging of contrast enhanced ultrasound. Gas-filled microbubbles were infused intravenously and by taking advantage of the echogenic properties of the microbubbles...... the resonating sound from the microbubbles in the systemic circulation were recorded for determination of microvascular recruitment in designated muscle segments. Results showed that microvascular recruitment increased with insulin stimulation by ~30% in rats and ~40% in humans (study I). Furthermore...... hormone glucagon-like-peptide-1 (GLP-1) in the microcirculation. Glucagon-like-peptide-1 analogs are drugs used for treatments of insulin resistance and type 2 diabetes but the vascular effects of GLP-1 in vivo are elusive. Here it was shown that GLP-1 rapidly increased the microvascular recruitment...
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Insulin is an anabolic hormone that plays key roles in glucose metabolism. Insulin resistance is a decreased biological response to normal concentration of circulating insulin. In insulin resistance, normal amounts of insulin are inadequate to produce a normal insulin response from fat, muscle and liver cells. Insulin ...
Ida-1, the Caenorhabditis elegans orthologue of mammalian diabetes autoantigen IA-2, potentially acts as a common modulator between Parkinson's disease and Diabetes: role of Daf-2/Daf-16 insulin like signalling pathway.
Fatima, Soobiya; Haque, Rizwanul; Jadiya, Pooja; Shamsuzzama; Kumar, Lalit; Nazir, Aamir
The lack of cure to age associated Parkinson's disease (PD) has been challenging the efforts of researchers as well as health care providers. Recent evidences suggest that diabetic patients tend to show a higher future risk for PD advocating a strong correlation between PD and Diabetes, thus making it intriguing to decipher common genetic cues behind these ailments. We carried out studies on ida-1, the C. elegans orthologue of mammalian type-1 diabetes auto-antigen IA-2 towards achieving its functional workup vis-à-vis various associated endpoints of PD and Diabetes. Employing transgenic C. elegans strain expressing "human" alpha synuclein (NL5901) under normal and increased glucose concentrations, we studied aggregation of alpha synuclein, content of dopamine, expression of dopamine transporter, content of reactive oxygen species, locomotor activity, nuclear translocation of FOXO transcription factor Daf-16, and quantification of Daf2/Daf-16 mRNA. Our findings indicate that ida-1 affords protection in the studied disease conditions as absence of ida-1 resulted in higher alpha-synuclein aggregation under conditions that mimic the blood glucose levels of diabetic patients. We also observed reduced dopamine content, decreased motility, defective Daf-16 translocation and reduced expression of Daf-2 and Daf-16. Our studies establish important function of ida-1 as a modulator in Daf-2/Daf-16 insulin like signalling pathway thus possibly being a common link between PD and Diabetes.
Ida-1, the Caenorhabditis elegans Orthologue of Mammalian Diabetes Autoantigen IA-2, Potentially Acts as a Common Modulator between Parkinson’s Disease and Diabetes: Role of Daf-2/Daf-16 Insulin Like Signalling Pathway
Fatima, Soobiya; Haque, Rizwanul; Jadiya, Pooja; Shamsuzzama; Kumar, Lalit; Nazir, Aamir
The lack of cure to age associated Parkinson’s disease (PD) has been challenging the efforts of researchers as well as health care providers. Recent evidences suggest that diabetic patients tend to show a higher future risk for PD advocating a strong correlation between PD and Diabetes, thus making it intriguing to decipher common genetic cues behind these ailments. We carried out studies on ida-1, the C. elegans orthologue of mammalian type-1 diabetes auto-antigen IA-2 towards achieving its functional workup vis-à-vis various associated endpoints of PD and Diabetes. Employing transgenic C. elegans strain expressing “human” alpha synuclein (NL5901) under normal and increased glucose concentrations, we studied aggregation of alpha synuclein, content of dopamine, expression of dopamine transporter, content of reactive oxygen species, locomotor activity, nuclear translocation of FOXO transcription factor Daf-16, and quantification of Daf2/Daf-16 mRNA. Our findings indicate that ida-1 affords protection in the studied disease conditions as absence of ida-1 resulted in higher alpha-synuclein aggregation under conditions that mimic the blood glucose levels of diabetic patients. We also observed reduced dopamine content, decreased motility, defective Daf-16 translocation and reduced expression of Daf-2 and Daf-16. Our studies establish important function of ida-1 as a modulator in Daf-2/Daf-16 insulin like signalling pathway thus possibly being a common link between PD and Diabetes. PMID:25469508
Ida-1, the Caenorhabditis elegans orthologue of mammalian diabetes autoantigen IA-2, potentially acts as a common modulator between Parkinson's disease and Diabetes: role of Daf-2/Daf-16 insulin like signalling pathway.
Full Text Available The lack of cure to age associated Parkinson's disease (PD has been challenging the efforts of researchers as well as health care providers. Recent evidences suggest that diabetic patients tend to show a higher future risk for PD advocating a strong correlation between PD and Diabetes, thus making it intriguing to decipher common genetic cues behind these ailments. We carried out studies on ida-1, the C. elegans orthologue of mammalian type-1 diabetes auto-antigen IA-2 towards achieving its functional workup vis-à-vis various associated endpoints of PD and Diabetes. Employing transgenic C. elegans strain expressing "human" alpha synuclein (NL5901 under normal and increased glucose concentrations, we studied aggregation of alpha synuclein, content of dopamine, expression of dopamine transporter, content of reactive oxygen species, locomotor activity, nuclear translocation of FOXO transcription factor Daf-16, and quantification of Daf2/Daf-16 mRNA. Our findings indicate that ida-1 affords protection in the studied disease conditions as absence of ida-1 resulted in higher alpha-synuclein aggregation under conditions that mimic the blood glucose levels of diabetic patients. We also observed reduced dopamine content, decreased motility, defective Daf-16 translocation and reduced expression of Daf-2 and Daf-16. Our studies establish important function of ida-1 as a modulator in Daf-2/Daf-16 insulin like signalling pathway thus possibly being a common link between PD and Diabetes.
Song, Ruisheng; Peng, Wei; Zhang, Yan; Lv, Fengxiang; Wu, Hong-Kun; Guo, Jiaojiao; Cao, Yongxing; Pi, Yanbin; Zhang, Xin; Jin, Li; Zhang, Mao; Jiang, Peng; Liu, Fenghua; Meng, Shaoshuai; Zhang, Xiuqin; Jiang, Ping; Cao, Chun-Mei; Xiao, Rui-Ping
Insulin resistance is a fundamental pathogenic factor present in various metabolic disorders including obesity and type 2 diabetes. Although skeletal muscle accounts for 70-90% of insulin-stimulated glucose disposal, the mechanism underlying muscle insulin resistance is poorly understood. Here we show in mice that muscle-specific mitsugumin 53 (MG53; also called TRIM72) mediates the degradation of the insulin receptor and insulin receptor substrate 1 (IRS1), and when upregulated, causes metabolic syndrome featuring insulin resistance, obesity, hypertension and dyslipidaemia. MG53 expression is markedly elevated in models of insulin resistance, and MG53 overexpression suffices to trigger muscle insulin resistance and metabolic syndrome sequentially. Conversely, ablation of MG53 prevents diet-induced metabolic syndrome by preserving the insulin receptor, IRS1 and insulin signalling integrity. Mechanistically, MG53 acts as an E3 ligase targeting the insulin receptor and IRS1 for ubiquitin-dependent degradation, comprising a central mechanism controlling insulin signal strength in skeletal muscle. These findings define MG53 as a novel therapeutic target for treating metabolic disorders and associated cardiovascular complications.
Philips, Jean-Christophe; Scheen, André
Insulin detemir is a soluble long-acting human insulin analogue at neutral pH with a unique mechanism of action. Following subcutaneous injection, insulin detemir binds to albumin via fatty acid chain, thereby providing slow absorption and a prolonged metabolic effect. Insulin detemir has a less variable pharmacokinetic profile than insulin suspension isophane or insulin ultralente. The use of insulin detemir can reduce the risk of hypoglycemia (especially nocturnal hypoglycemia) in type 1 and type 2 diabetic patients. However, overall glycemic control, as assessed by glycated hemoglobin, is only marginally and not significantly improved compared with usual insulin therapy. The weight gain commonly associated with insulin therapy is rather limited when insulin detemir is used. In our experience, this new insulin analogue is preferably administrated at bedtime but can be proposed twice a day (in the morning and either before the dinner or at bedtime). Detemir is a promising option for basal insulin therapy in type 1 or type 2 diabetic patients. PMID:17326333
Leloup, Corinne; Tourrel-Cuzin, C?cile; Magnan, Christophe; Karaca, Melis; Castel, Julien; Carneiro, Lionel; Colombani, Anne-Laure; Ktorza, Alain; Casteilla, Louis; P?nicaud, Luc
OBJECTIVE?Insulin secretion involves complex events in which the mitochondria play a pivotal role in the generation of signals that couple glucose detection to insulin secretion. Studies on the mitochondrial generation of reactive oxygen species (ROS) generally focus on chronic nutrient exposure. Here, we investigate whether transient mitochondrial ROS production linked to glucose-induced increased respiration might act as a signal for monitoring insulin secretion. RESEARCH DESIGN AND METHODS...
Full Text Available Lutvo KuricNovi Travnik, Kalinska, Bosnia and Herzegovina Abstract: This paper discusses cyberinformation studies of the amino acid composition of insulin, in particular the identification of scientific terminology that could describe this phenomenon, ie, the study of genetic information, as well as the relationship between the genetic language of proteins and theoretical aspects of this system and cybernetics. The results of this research show that there is a matrix code for insulin. It also shows that the coding system within the amino acid language gives detailed information, not only on the amino acid “record”, but also on its structure, configuration, and various shapes. The issue of the existence of an insulin code and coding of the individual structural elements of this protein are discussed. Answers to the following questions are sought. Does the matrix mechanism for biosynthesis of this protein function within the law of the general theory of information systems, and what is the significance of this for understanding the genetic language of insulin? What is the essence of existence and functioning of this language? Is the genetic information characterized only by biochemical principles or it is also characterized by cyberinformation principles? The potential effects of physical and chemical, as well as cybernetic and information principles, on the biochemical basis of insulin are also investigated. This paper discusses new methods for developing genetic technologies, in particular more advanced digital technology based on programming, cybernetics, and informational laws and systems, and how this new technology could be useful in medicine, bioinformatics, genetics, biochemistry, and other natural sciences.Keywords: human insulin, insulin model, biocode, genetic code, amino acids
Labouèbe, Gwenaël; Liu, Shuai; Dias, Carine; Zou, Haiyan; Wong, Jovi C.Y.; Karunakaran, Subashini; Clee, Susanne M.; Phillips, Anthony; Boutrel, Benjamin; Borgland, Stephanie L.
The prevalence of obesity has drastically increased over the last few decades. Exploration into how hunger and satiety signals influence the reward system can help us to understand non-homeostatic mechanisms of feeding. Evidence suggests that insulin may act in the ventral tegmental area (VTA), a critical site for reward-seeking behavior, to suppress feeding. However, the neural mechanisms underlying insulin effects in the VTA remain unknown. We demonstrate that insulin, a circulating catabolic peptide that inhibits feeding, can induce a long-term depression (LTD) of excitatory synapses onto VTA dopamine neurons. This effect requires endocannabinoid-mediated presynaptic inhibition of glutamate release. Furthermore, after a sweetened high fat meal, which elevates endogenous insulin levels, insulin-induced LTD is occluded. Finally, insulin in the VTA reduces food anticipatory behavior and conditioned place preference for food. Taken together, these results suggest that insulin in the VTA suppresses excitatory synaptic transmission and reduces salience of food-related cues. PMID:23354329
Nault, Laurent; Vendrely, Charlotte; Bréchet, Yves; Bruckert, Franz; Weidenhaupt, Marianne
Interactions between proteins and material or cellular surfaces are able to trigger protein aggregation in vitro and in vivo. The human insulin peptide segment LVEALYL is able to accelerate insulin aggregation in the presence of hydrophobic surfaces. We show that this peptide needs to be previously adsorbed on a hydrophobic surface to induce insulin aggregation. Moreover, the study of different mutant peptides proves that its sequence is less important than the secondary structure of the adsorbed peptide on the surface. Indeed, these pro-aggregative peptides act by providing stable β-sheets to incoming insulin molecules, thereby accelerating insulin adsorption locally and facilitating the conformational changes required for insulin aggregation. Conversely, a peptide known to form α-helices on hydrophobic surfaces delays insulin aggregation. Copyright © 2013 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.
Campbell, Matthew D; Walker, Mark; Bracken, Richard M; Turner, Daniel; Stevenson, Emma J; Gonzalez, Javier T; Shaw, James A; West, Daniel J
Evening-time exercise is a frequent cause of severe hypoglycemia in type 1 diabetes, fear of which deters participation in regular exercise. Recommendations for normalizing glycemia around exercise consist of prandial adjustments to bolus insulin therapy and food composition, but this carries only short-lasting protection from hypoglycemia. Therefore, this study aimed to examine the impact of a combined basal-bolus insulin dose reduction and carbohydrate feeding strategy on glycemia and metabolic parameters following evening exercise in type 1 diabetes. Ten male participants (glycated hemoglobin: 52.4±2.2 mmol/mol), treated with multiple daily injections, completed two randomized study-days, whereby administration of total daily basal insulin dose was unchanged (100%), or reduced by 20% (80%). Participants attended the laboratory at ∼08:00 h for a fasted blood sample, before returning in the evening. On arrival (∼17:00 h), participants consumed a carbohydrate meal and administered a 75% reduced rapid-acting insulin dose and 60 min later performed 45 min of treadmill running. At 60 min postexercise, participants consumed a low glycemic index (LGI) meal and administered a 50% reduced rapid-acting insulin dose, before returning home. At ∼23:00 h, participants consumed a LGI bedtime snack and returned to the laboratory the following morning (∼08:00 h) for a fasted blood sample. Venous blood samples were analyzed for glucose, glucoregulatory hormones, non-esterified fatty acids, β-hydroxybutyrate, interleukin 6, and tumor necrosis factor α. Interstitial glucose was monitored for 24 h pre-exercise and postexercise. Glycemia was similar until 6 h postexercise, with no hypoglycemic episodes. Beyond 6 h glucose levels fell during 100%, and nine participants experienced nocturnal hypoglycemia. Conversely, all participants during 80% were protected from nocturnal hypoglycemia, and remained protected for 24 h postexercise. All metabolic
Gancheva, Sofiya; Koliaki, Chrysi; Bierwagen, Alessandra; Nowotny, Peter; Heni, Martin; Fritsche, Andreas; Häring, Hans-Ulrich; Szendroedi, Julia; Roden, Michael
Studies in rodents suggest that insulin controls hepatic glucose metabolism through brain-liver crosstalk, but human studies using intranasal insulin to mimic central insulin delivery have provided conflicting results. In this randomized controlled crossover trial, we investigated the effects of intranasal insulin on hepatic insulin sensitivity (HIS) and energy metabolism in 10 patients with type 2 diabetes and 10 lean healthy participants (CON). Endogenous glucose production was monitored with [6,6-(2)H2]glucose, hepatocellular lipids (HCLs), ATP, and inorganic phosphate concentrations with (1)H/(31)P magnetic resonance spectroscopy. Intranasal insulin transiently increased serum insulin levels followed by a gradual lowering of blood glucose in CON only. Fasting HIS index was not affected by intranasal insulin in CON and patients. HCLs decreased by 35% in CON only, whereas absolute hepatic ATP concentration increased by 18% after 3 h. A subgroup of CON received intravenous insulin to mimic the changes in serum insulin and blood glucose levels observed after intranasal insulin. This resulted in a 34% increase in HCLs without altering hepatic ATP concentrations. In conclusion, intranasal insulin does not affect HIS but rapidly improves hepatic energy metabolism in healthy humans, which is independent of peripheral insulinemia. These effects are blunted in patients with type 2 diabetes. © 2015 by the American Diabetes Association. Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered.
Richter, Erik; Hansen, B F; Hansen, S A
, impairment of insulin action on muscle glucose transport and uptake. Thus maximal insulin-stimulated glucose uptake at 12 mM-glucose decreased from 34.8 +/- 1.9 to 11.5 +/- 1.1 mumol/h per g (mean +/- S.E.M., n = 10) during 5 h perfusion. This decrease in glucose uptake was accompanied by a similar change...... in the presence of glucose and insulin. The data indicate that exposure to a moderately increased glucose concentration (12 mM) leads to rapidly developing resistance of skeletal-muscle glucose transport and uptake to maximal insulin stimulation. The effect of glucose is enhanced by simultaneous insulin exposure......, whereas exposure for 5 h to insulin itself does not cause measurable resistance to maximal insulin stimulation....
Full Text Available As the linker between the A chain and B chain of proinsulin, C-peptide displays high variability in length and amino acid composition, and has been considered as an inert byproduct of insulin synthesis and processing for many years. Recent studies have suggested that C-peptide can act as a bioactive hormone, exerting various biological effects on the pathophysiology and treatment of diabetes. In this study, we analyzed the coevolution of insulin molecules among vertebrates, aiming at exploring the evolutionary characteristics of insulin molecule, especially the C-peptide. We also calculated the correlations of evolutionary rates between the insulin and the insulin receptor (IR sequences as well as the domain-domain pairs of the ligand and receptor by the mirrortree method. The results revealed distinctive features of C-peptide in insulin intramolecular coevolution and correlated residue substitutions, which partly supported the idea that C-peptide can act as a bioactive hormone, with significant sequence features, as well as a linker assisting the formation of mature insulin during synthesis. Interestingly, the evolution of C-peptide exerted the highest correlation with that of the insulin receptor and its ligand binding domain (LBD, implying a potential relationship with the insulin signaling pathway.
Wang, Shuai; Wei, Wei; Zheng, Yadong; Hou, Junling; Dou, Yongxi; Zhang, Shaohua; Luo, Xuenong; Cai, Xuepeng
As the linker between the A chain and B chain of proinsulin, C-peptide displays high variability in length and amino acid composition, and has been considered as an inert byproduct of insulin synthesis and processing for many years. Recent studies have suggested that C-peptide can act as a bioactive hormone, exerting various biological effects on the pathophysiology and treatment of diabetes. In this study, we analyzed the coevolution of insulin molecules among vertebrates, aiming at exploring the evolutionary characteristics of insulin molecule, especially the C-peptide. We also calculated the correlations of evolutionary rates between the insulin and the insulin receptor (IR) sequences as well as the domain-domain pairs of the ligand and receptor by the mirrortree method. The results revealed distinctive features of C-peptide in insulin intramolecular coevolution and correlated residue substitutions, which partly supported the idea that C-peptide can act as a bioactive hormone, with significant sequence features, as well as a linker assisting the formation of mature insulin during synthesis. Interestingly, the evolution of C-peptide exerted the highest correlation with that of the insulin receptor and its ligand binding domain (LBD), implying a potential relationship with the insulin signaling pathway.
Frøsig, Christian; Richter, Erik
After a single bout of exercise, the ability of insulin to stimulate glucose uptake is markedly improved locally in the previously active muscles. This makes exercise a potent stimulus counteracting insulin resistance characterizing type 2 diabetes (T2D). It is believed that at least part...... of the mechanism relates to an improved ability of insulin to stimulate translocation of glucose transporters (GLUT4) to the muscle membrane after exercise. How this is accomplished is still unclear; however, an obvious possibility is that exercise interacts with the insulin signaling pathway to GLUT4...... translocation allowing for a more potent insulin response. Parallel to unraveling of the insulin signaling cascade, this has been investigated within the past 25 years. Reviewing existing studies clearly indicates that improved insulin action can occur independent of interactions with proximal insulin signaling...
Swinnen, Sanne G.; Simon, Airin C. R.; Holleman, Frits; Hoekstra, Joost B.; DeVries, J. Hans
Chronically elevated blood glucose levels are associated with significant morbidity and mortality. Many diabetes patients will eventually require insulin treatment to maintain good glycaemic control. There are still uncertainties about the optimal insulin treatment regimens for type 2 diabetes, but
Velez, Mauricio; Kohli, Smita; Sabbah, Hani N.
The incidence of heart failure (HF) and diabetes mellitus is rapidly increasing and is associated with poor prognosis. In spite of the advances in therapy, HF remains a major health problem with high morbidity and mortality. When HF and diabetes coexist, clinical outcomes are significantly worse. The relationship between these two conditions has been studied in various experimental models. However, the mechanisms for this interrelationship are complex, incompletely understood, and have become a matter of considerable clinical and research interest. There are only few animal models that manifest both HF and diabetes. However, the translation of results from these models to human disease is limited and new models are needed to expand our current understanding of this clinical interaction. In this review, we discuss mechanisms of insulin signaling and insulin resistance, the clinical association between insulin resistance and HF and its proposed pathophysiologic mechanisms. Finally, we discuss available animal models of insulin resistance and HF and propose requirements for future new models. PMID:23456447
Mathieu, Chantal; Gillard, Pieter; Benhalima, Katrien
The treatment of type 1 diabetes mellitus consists of external replacement of the functions of β cells in an attempt to achieve blood levels of glucose as close to the normal range as possible. This approach means that glucose sensing needs to be replaced and levels of insulin need to mimic physiological insulin-action profiles, including basal coverage and changes around meals. Training and educating patients are crucial for the achievement of good glycaemic control, but having insulin preparations with action profiles that provide stable basal insulin coverage and appropriate mealtime insulin peaks helps people with type 1 diabetes mellitus to live active lives without sacrificing tight glycaemic control. Insulin analogues enable patients to achieve this goal, as some have fast action profiles, and some have very slow action profiles, which gives people with type 1 diabetes mellitus the tools to achieve dynamic insulin-action profiles that enable tight glycaemic control with a risk of hypoglycaemia that is lower than that with human short-acting and long-acting insulins. This Review discusses the established and novel insulin analogues that are used to treat patients with type 1 diabetes mellitus and provides insights into the future development of insulin analogues.
Hildebrant, P; Mehlsen, J; Birch, K
To study the relationship between the absorption of intermediate acting insulin and the local subcutaneous blood flow (SBF) 8 diabetic patients were given subcutaneous injections of 125I labeled human lente type insulin and 133Xenon in the abdominal wall. External measurements of the tracer...
Siddiqui, N I; Siddiqui, Ni; Rahman, S; Nessa, A
Delivery system of insulin is vital for its acceptance and adherence to therapy for achieving the glycemic targets. Enormous developments have occurred in the delivery system of insulin during the last twenty years and each improvement was aimed at two common goals: patients convenience and better glycemic control. Till to date, the various insulin delivery systems are: syringes/vials, injection aids, jet injectors, transmucosal delivery, transdermal delivery, external insulin infusion pump, implantable insulin pumps, insulin pens and insulin inhalers. Syringe/vial is the oldest and conventional method, still widely used and relatively cheaper. Modern plastic syringes are disposable, light weight with microfine needle for patients convenience and comfort. Oral route could be the most acceptable and viable, if the barriers can be overcome and under extensive trial. Insulin pen device is an important milestone in the delivery system of insulin as it is convenient, discrete, painless, attractive, portable with flexible life style and improved quality of life. More than 80% of European diabetic patients are using insulin pen. Future digital pen will have better memory option, blood glucose monitoring system, insulin dose calculator etc. Insulin infusion pump is a good option for the children, busy patients with flexible lifestyle and those who want to avoid multiple daily injections. Pulmonary route of insulin delivery is a promising, effective, non-invasive and acceptable alternative method. Exubera, the world first insulin inhaler was approved by FDA in 28 January 2006. But due to certain limitations, it has been withdrawn from the market in October 2007. The main concern of inhaled insulin are: long term pulmonary safety issues, cost effectiveness and user friendly device. In future, more acceptable and cost effective insulin inhaler will be introduced. Newer avenues are under extensive trial for better future insulin delivery systems.
Lassmann-Vague, V; Clavel, S; Guerci, B; Hanaire, H; Leroy, R; Loeuille, G A; Mantovani, I; Pinget, M; Renard, E; Tubiana-Rufi, N
For years, external insulin pumps have enjoyed proven efficacy as an intensive diabetes treatment to improve glycaemic control and reduce hypoglycaemia. Since the last ALFEDIAM guidelines in 1995, however, basal-bolus treatment using a combination of long- and short-acting insulin analogues have emerged and could challenge, at a lower cost, the efficacy of pumps using rapid-acting insulin analogues, considered the 'gold standard' of insulin treatment. Nevertheless, given its theoretical and practical advantages, some patients will derive more benefit from pump treatment. These cases have been carefully evaluated in the literature by a panel of experts appointed by ALFEDIAM to determine the indications for pump treatment. In patients with type 1 diabetes, persistent elevated HbA(1c) despite multiple daily injections (MDI), and repeated hypoglycaemia and high glycaemic variability, represent the most validated indications. In patients with type 2 diabetes, pump treatment may be indicated in cases of MDI failure to achieve HbA(1c) targets. Absolute contraindications are rare, and comprise severe psychiatric disorders, rapidly progressing ischaemic or proliferative retinopathy before laser treatment and exposure to high magnetic fields. Relative contraindications are mostly related to the patient's lack of compliance or inability to cope with the treatment, and need to be evaluated individually to clearly assess the benefit/risk ratio for the given patient. However, as these conditions are progressive, there should also be annual reassessment of the appropriateness of pump treatment. Specific education on pump treatment initially and throughout the follow-up, delivered by experienced medical and paramedical teams, are the best guarantees of treatment efficacy and safety. Copyright (c) 2010 Elsevier Masson SAS. All rights reserved.
Córdoba-Chacón, Jose; Gahete, Manuel D; Pozo-Salas, Ana I; Castaño, Justo P; Kineman, Rhonda D; Luque, Raul M
l-arginine (l-Arg) rapidly stimulates GH and insulin release in vivo. It has been hypothesized that l-Arg stimulates GH release by lowering hypothalamic somatostatin (SST) tone. l-Arg may also act directly at the pituitary to stimulate GH release. Moreover, l-Arg has a direct stimulatory effect on β-cells, which is thought to be blunted by the release of SST from pancreatic δ-cells. To confirm the role of endogenous SST on l-Arg-induced GH and insulin release, wild-type (WT) and SST-knockout (SST-KO) mice were injected with l-Arg (ip; 0.8 g/kg), and pre-/post-injection GH, insulin, and glucose levels were measured. In WT mice, l-Arg evoked a 6-fold increase in circulating GH. However, there was only a modest increase in GH levels in WT pituitary cell cultures treated with l-Arg. In contrast, l-Arg failed to increase GH in SST-KO beyond their already elevated levels. These results further support the hypothesis that the primary mechanism by which l-Arg acutely increases GH in vivo is by lowering hypothalamic SST input to the pituitary and not via direct pituitary effects. Additionally, l-Arg induced a clear first-phase insulin secretion in WT mice, but not in SST-KO. However, SST-KO, but not WT mice, displayed a robust and sustained second-phase insulin release. These results further support a role for endogenous SST in regulating l-Arg-mediated insulin release.
Huus, Kasper; Havelund, Svend; Olsen, Helle B
To study the correlation between the thermal and chemical stability of insulin formulations with various insulin hexamer ligands.......To study the correlation between the thermal and chemical stability of insulin formulations with various insulin hexamer ligands....
Filipsson, K; Pacini, G; Scheurink, AJW; Ahren, B
Although pituitary adenylate cyclase-activating polypeptide (PACAP) stimulates insulin secretion, its net influence on glucose homeostasis in vivo has not been established. We therefore examined the action of PACAP-27 and PACAP-38 on insulin secretion, insulin sensitivity, and glucose disposal as
Comparison of a Multiple Daily Insulin Injection Regimen (Glargine or Detemir Once Daily Plus Prandial Insulin Aspart and Continuous Subcutaneous Insulin Infusion (Aspart in Short-Term Intensive Insulin Therapy for Poorly Controlled Type 2 Diabetes Patients
Full Text Available Aims. To examine the potential differences between multiple daily injection (MDI regimens based on new long-acting insulin analogues (glargine or detemir plus prandial insulin aspart and continuous subcutaneous insulin aspart infusion (CSII in patients with poorly controlled type 2 diabetes. Methods. Patients (n=119 with poorly controlled type 2 diabetes of a duration exceeding five years were randomly assigned into three groups: Group A treated with CSII using insulin aspart; Group B treated with glargine-based MDI and Group C treated with detemir-based MDI. Results. Good glycemic control was achieved by patients in Group A in a significantly shorter duration than patients in Groups B and C. Total daily insulin, basal insulin dose and dose per kg body weight in Group A were significantly less than those in Groups B and C. Daily blood glucose fluctuation in Group A was significantly less than that in Groups B and C. There were no differences between Groups B and C. Conclusions. Aspart-based CSII may achieve good blood glucose control with less insulin doses over a shorter period compared with glargine or detemir-based MDI. No differences between glargine- and detemir-based MDI were detected in poorly controlled subjects with type 2 diabetes.
Pouwer, Francois; Hermanns, Norbert
Three central goals in the treatment of diabetes mellitus are (1) the avoidance of hyperglycaemia to prevent the development or progression of diabetes complications over time, (2) the avoidance of hypoglycaemia and (3) the maintenance or achievement of good quality of life. Insulin is the most......-acting insulin analogues or biphasic mixtures; (3) multiple daily injections versus pump therapy. Having multiple complications of diabetes is clearly associated with decreased QoL. Results from large studies such as the Diabetes Control and Complications Trial (DCCT) and United Kingdom Prospective Diabetes...... powerful agent that can be used to control blood glucose levels. This article reviews the studies that have investigated the effects of different types of insulin and insulin delivery techniques on quality of life of patients with type 1 or type 2 diabetes. First, the concept of 'quality of life' (Qo...
Full Text Available BACKGROUND: The interactions between the insulin signaling pathway (ISP and juvenile hormone (JH controlling reproductive trade-offs are well documented in insects. JH and insulin regulate reproductive output in mosquitoes; both hormones are involved in a complex regulatory network, in which they influence each other and in which the mosquito's nutritional status is a crucial determinant of the network's output. Previous studies reported that the insulin-TOR (target of rapamacyn signaling pathway is involved in the nutritional regulation of JH synthesis in female mosquitoes. The present studies further investigate the regulatory circuitry that controls both JH synthesis and reproductive output in response to nutrient availability. METHODS: We used a combination of diet restriction, RNA interference (RNAi and insulin treatments to modify insulin signaling and study the cross-talk between insulin and JH in response to starvation. JH synthesis was analyzed using a newly developed assay utilizing fluorescent tags. CONCLUSIONS: Our results reveal that starvation decreased JH synthesis via a decrease in insulin signaling in the corpora allata (CA. Paradoxically, starvation-induced up regulation of insulin receptor transcripts and therefore "primed" the gland to respond rapidly to increases in insulin levels. During this response to starvation the synthetic potential of the CA remained unaffected, and the gland rapidly and efficiently responded to insulin stimulation by increasing JH synthesis to rates similar to those of CA from non-starved females.
Full Text Available The OB protein, also known as leptin, is secreted by adipose tissue, circulates in the blood, probably bound to a family of binding proteins, and acts on central neural networks regulating ingestive behavior and energy balance. The two forms of leptin receptors (long and short forms have been identified in various peripheral tissues, a fact that makes them possible target sites for a direct action of leptin. It has been shown that the OB protein interferes with insulin secretion from pancreatic islets, reduces insulin-stimulated glucose transport in adipocytes, and increases glucose transport, glycogen synthesis and fatty acid oxidation in skeletal muscle. Under normoglycemic and normoinsulinemic conditions, leptin seems to shift the flux of metabolites from adipose tissue to skeletal muscle. This may function as a peripheral mechanism that helps control body weight and prevents obesity. Data that substantiate this hypothesis are presented in this review.
Huckvale, Kit; Adomaviciute, Samanta; Prieto, José Tomás; Leow, Melvin Khee-Shing; Car, Josip
Medical apps are widely available, increasingly used by patients and clinicians, and are being actively promoted for use in routine care. However, there is little systematic evidence exploring possible risks associated with apps intended for patient use. Because self-medication errors are a recognized source of avoidable harm, apps that affect medication use, such as dose calculators, deserve particular scrutiny. We explored the accuracy and clinical suitability of apps for calculating medication doses, focusing on insulin calculators for patients with diabetes as a representative use for a prevalent long-term condition. We performed a systematic assessment of all English-language rapid/short-acting insulin dose calculators available for iOS and Android. Searches identified 46 calculators that performed simple mathematical operations using planned carbohydrate intake and measured blood glucose. While 59% (n = 27/46) of apps included a clinical disclaimer, only 30% (n = 14/46) documented the calculation formula. 91% (n = 42/46) lacked numeric input validation, 59% (n = 27/46) allowed calculation when one or more values were missing, 48% (n = 22/46) used ambiguous terminology, 9% (n = 4/46) did not use adequate numeric precision and 4% (n = 2/46) did not store parameters faithfully. 67% (n = 31/46) of apps carried a risk of inappropriate output dose recommendation that either violated basic clinical assumptions (48%, n = 22/46) or did not match a stated formula (14%, n = 3/21) or correctly update in response to changing user inputs (37%, n = 17/46). Only one app, for iOS, was issue-free according to our criteria. No significant differences were observed in issue prevalence by payment model or platform. The majority of insulin dose calculator apps provide no protection against, and may actively contribute to, incorrect or inappropriate dose recommendations that put current users at risk of both catastrophic overdose and more
Wang, Hong; Upchurch, Charles T.; Liu, Zhenqi
Insulin, at physiological concentrations, regulates the volume of microvasculature perfused within skeletal and cardiac muscle. It can also, by relaxing the larger resistance vessels, increase total muscle blood flow. Both of these effects require endothelial cell nitric oxide generation and smooth muscle cell relaxation, and each could increase delivery of insulin and nutrients to muscle. The capillary microvasculature possesses the greatest endothelial surface area of the body. Yet, whether insulin acts on the capillary endothelial cell is not known. Here, we review insulin's actions at each of three levels of the arterial vasculature as well as recent data suggesting that insulin can regulate a vesicular transport system within the endothelial cell. This latter action, if it occurs at the capillary level, could enhance insulin delivery to muscle interstitium and thereby complement insulin's actions on arteriolar endothelium to increase insulin delivery. We also review work that suggests that this action of insulin on vesicle transport depends on endothelial cell nitric oxide generation and that insulin's ability to regulate this vesicular transport system is impaired by inflammatory cytokines that provoke insulin resistance. PMID:21610226
Dridi, Larbi; Seyrantepe, Volkan; Fougerat, Anne; Pan, Xuefang; Bonneil, Eric; Thibault, Pierre; Moreau, Allain; Mitchell, Grant A; Heveker, Nikolaus; Cairo, Christopher W; Issad, Tarik; Hinek, Alexander; Pshezhetsky, Alexey V
Neuraminidases (sialidases) catalyze the removal of sialic acid residues from sialylated glycoconjugates. We now report that mammalian neuraminidase 1 (Neu1), in addition to its catabolic function in lysosomes, is transported to the cell surface where it is involved in the regulation of insulin signaling. Insulin binding to its receptor rapidly induces interaction of the receptor with Neu1, which hydrolyzes sialic acid residues in the glycan chains of the receptor and, consequently, induces its activation. Cells from sialidosis patients with a genetic deficiency of Neu1 show impairment of insulin-induced phosphorylation of downstream protein kinase AKT, and treatment of these cells with purified Neu1 restores signaling. Genetically modified mice with ∼10% of the normal Neu1 activity exposed to a high-fat diet develop hyperglycemia and insulin resistance twice as fast as their wild-type counterparts. Together, these studies identify Neu1 as a novel component of the signaling pathways of energy metabolism and glucose uptake.
Insulin is a major protein hormone secreted by the p-cells of the pancreas and is important for the control of diabetes. Insulin is usually administered to diabetic patients through subcutaneous injection. This mode of therapy has certain inherent disadvantages such as local pain, itching and insulin lipodystrophy around the ...
Free fatty acids are known to play a key role in promoting loss of insulin sensitivity, thereby causing insulin resistance and type 2 diabetes. However, the underlying mechanism involved is still unclear. In searching for the cause of the mechanism, it has been found that palmitate inhibits insulin receptor (IR) gene expression, ...
Dineley, Kelly T; Jahrling, Jordan B; Denner, Larry
Insulin is a key hormone regulating metabolism. Insulin binding to cell surface insulin receptors engages many signaling intermediates operating in parallel and in series to control glucose, energy, and lipids while also regulating mitogenesis and development. Perturbations in the function of any of these intermediates, which occur in a variety of diseases, cause reduced sensitivity to insulin and insulin resistance with consequent metabolic dysfunction. Chronic inflammation ensues which exacerbates compromised metabolic homeostasis. Since insulin has a key role in learning and memory as well as directly regulating ERK, a kinase required for the type of learning and memory compromised in early Alzheimer's disease (AD), insulin resistance has been identified as a major risk factor for the onset of AD. Animal models of AD or insulin resistance or both demonstrate that AD pathology and impaired insulin signaling form a reciprocal relationship. Of note are human and animal model studies geared toward improving insulin resistance that have led to the identification of the nuclear receptor and transcription factor, peroxisome proliferator-activated receptor gamma (PPARγ) as an intervention tool for early AD. Strategic targeting of alternate nodes within the insulin signaling network has revealed disease-stage therapeutic windows in animal models that coalesce with previous and ongoing clinical trial approaches. Thus, exploiting the connection between insulin resistance and AD provides powerful opportunities to delineate therapeutic interventions that slow or block the pathogenesis of AD. PMID:25237037
basis of insulin resistance could ultimately lead to a better understanding of the causation of these conditions and the design of rational therapy to ameliorate them. Here, particular attention is devoted to the initial events that follow the binding of insulin to its receptor, including changes in insulin receptor phosphorylation.
... Content View Sources Ask Us Also Known As ACT Activated Coagulation Time Formal Name Activated Clotting Time ... What is being tested? The activated clotting time (ACT) is a test that is used primarily to ...
Lassen, Aske Juul
grænser nedbrydes i en konstant penetrering af huden, når blodsukkeret måles eller insulinen indsprøjtes. Insulin analyseres som en tricksterfigur, der udøver et grænsearbejde på kroppen, leger med dens kategorier og vender forholdet mellem gift og medicin, frihed og ufrihed, kunstighed og naturlighed...
Yki-Järvinen, H; Ryysy, L; Nikkilä, K; Tulokas, T; Vanamo, R; Heikkilä, M
Compared with other insulin regimens, combination therapy with oral hypoglycemic agents and bedtime insulin produces similar improvement in glycemic control but induces less weight gain. To determine whether bedtime insulin regimens differ with respect to their effects on weight gain in patients with type 2 diabetes. Randomized, controlled trial. Four outpatient clinics at central hospitals. 96 patients (mean age, 58 +/- 1 years; mean body mass index, 29 +/- 1 kg/m2) whose type 2 diabetes was poorly controlled with sulfonylurea therapy (mean glycosylated hemoglobin value, 9.9% +/- 0.2%; mean fasting plasma glucose level, 11.9 +/- 0.3 mmol/L [214 +/- 5 mg/dL]). Random assignment to 1 year of treatment with bedtime intermediate-acting insulin plus glyburide (10.5 mg) and placebo, metformin (2 g) and placebo, glyburide and metformin, or a second injection of intermediate-acting insulin in the morning. Patients were taught to adjust the bedtime insulin dose on the basis of fasting glucose measurements. Body weight, biochemical and symptomatic hypoglycemias, and indices of glycemic control. At 1 year, body weight remained unchanged in patients receiving bedtime insulin plus metformin (mean change, 0.9 +/- 1.2 kg; P bedtime insulin plus glyburide, those receiving bedtime insulin plus both oral drugs, and those receiving bedtime and morning insulin, respectively. The greatest decrease in the glycosylated hemoglobin value was observed in the bedtime insulin and metformin group (from 9.7% +/- 0.4% to 7.2% +/- 0.2% [difference, -2.5 +/- 0.4 percentage points] at 1 year; P bedtime insulin plus metformin prevents weight gain. This regimen also seems superior to other bedtime insulin regimens with respect to improvement in glycemic control and frequency of hypoglycemia.
de Diabetes consensus documents. SUMMARY OF THE FINDINGS: Information is presented on new analogs of insulin and, for purposes of comparison, the other insulin modalities currently available are also reviewed, focusing on insulin therapies which attempt to approximate basal-bolus treatment strategies to physiology. With the objective of obtaining improved metabolic control, more and more children are being put on multiple daily injection regimes or using continuous subcutaneous insulin infusion. It is difficult to achieve optimum glycemic control in children due to the increased risk of hypoglycemia resulting from the great variability in dietary intake habits and in physical activity levels. With diabetes type 1, if rapid-acting analogs are given subcutaneously in bolus, they generally reduce hypoglycemia episodes and postprandial glycemia levels, compared with regular human insulin, while basal analogs tend to reduce particularly the number of episodes of nocturnal hypoglycemia. CONCLUSIONS: Although the benefits to individual metabolic and clinical outcomes appear modest, the majority of studies demonstrate benefits when insulin analogs are used in the treatment of diabetes type 1 or 2.
Full Text Available Backgound: The number of hypogonads is increasing day by day. It may be due to sedentary life style with increased obesity, increased tension or stressed lifestyle among all groups of populations. Visceral obesity is associated with insulin resistance, diabetes mellitus and also with hypogonadism.Objective: This study was carried out to determine the proportion of insulin resistance among male subjects with hypogonadism in different age groups along with status of erectile quality among diabetics and non diabetics.Materials and method: This cross sectional study among 161 adult male subjects aged ≥ 20 to ≤ 60 years were purposively selected from Bangladesh Institute of Research and Rehabilitation in Diabetes Endocrine and Metabolic Disorders (BIRDEM, Dhaka, Bangladesh between May 2009 to September 2010. Glycemic status and insulin resistance (by HOMA-R were done and relevant history were documented.Results: The highest proportion (38.9% of hypogonadism was in ≥ 50 years age group whereas highest proportion (39.6% of the eugonads was in the age group of 40 to 49 years. More than half of the hypogonad subjects had weak erectile quality (54.0% which were followed by absent erectile quality in 32.7% and 13.3% subjects had normal erectile quality. Among the eugonad subjects 41.7% had normal erectile quality, 41.6% subjects had weak erectile quality and 16.7% subjects had no erectile quality. More than ninety percent of the hypogonad subjects and about 60% of the eugonad subjects had insulin resistance. The average HOMA-R was more in the subjects with hypogonadism with diabetes which was highly significant (p-value < 0.001.Conclusion: Hypogonadism is associated with insulin resistance.
Papa, Giuseppe; Baratta, Roberto; Calì, Vincenzo; Degano, Claudia; Iurato, Maria Pierangela; Licciardello, Carmelo; Maiorana, Raffaella; Finocchiaro, Concetta
In clinical practice, basal insulin dosage (BID) for the treatment for type 2 diabetes given as slow-acting analogues or NPH insulin varies widely when adjusted for body weight (UI/kg). In this study, we investigated the interrelationship between BID and anthropometric, laboratory and clinical parameters. A total of 681 type 2 diabetic patients, treated with bedtime insulin in association with other antidiabetic drugs (preprandial insulin and/or oral agents), were studied. Anthropometric, clinical and biochemical parameters, as well as micro- and macrovascular complications, were evaluated. Non-alcoholic fatty liver disease (NAFLD) was assessed by liver ultrasound. BID was titrated to achieve a fasting blood glucose target of ≤6.7 mmol/L (120 mg/dL). In the multivariate analysis, BID was significantly associated with waist circumference (p = 0.04) and the insulin treatment duration (p = 0.004) as the type of insulin treatment ("basal-bolus" regimen vs. basal insulin only, p < 0.0001), the use of lipid-lowering drugs (p = 0.0003) and insulin sensitizers (p = 0.005). Several glycometabolic parameters were strongly associated with BID (HbA1c p = 0.01, FPG p < 0.0001, HDL p = 0.02, triglycerides p = 0.03). Moreover, the presence of severe NAFLD resulted in a higher BID (p = 0.03). We concluded that when starting and titrating the basal insulin in type 2 diabetes, certain anthropometric, laboratory and clinical factors can be useful to find optimal BID more quickly and appropriately.
Khan Ghilzai, Naushad M
A vigorous research effort has been undertaken worldwide to replace injectable insulin by a more comfortable and painless delivery method. Several routes have been explored for their suitability with respect to insulin degradation in the human body. Considerable progress has been made in achieving the common goal for a convenient and equally effective insulin delivery. This article reviews the different routes available for insulin administration and the many successful developments that have been made in recent years for improving that particular route for a much better insulin delivery.
Obesity is a major risk factor for insulin resistance and type 2 diabetes. Adipose tissue is now considered to be an active endocrine organ that secretes various adipokines such as adiponectin, leptin, resistin, tumour necrosis factor-α, and interleukin-6. Recent studies have shown that these factors might provide a molecular link between increased adiposity and impaired insulin sensitivity. Since hepatic insulin resistance plays the key role in the whole body insulin resistance, clarification of the regulatory processes about hepatic insulin resistance by adipokines in rodents and human would seem essential in order to understand the mechanism of type 2 diabetes and for developing novel therapeutic strategies to treat it. PMID:23762871
Yared N Demssie
Full Text Available Yared N Demssie1, Naveed Younis2, Handrean Soran31Department of Diabetes and Endocrinology, Salford Royal Foundation NHS Trust, Salford, UK; 2Department of Medicine, University Hospital South Manchester Foundation NHS Trust, Wythenshawe, Manchester, UK; 3University Department of Medicine, Central Manchester and Manchester Children’s NHS Foundation Trust, Manchester, UKAbstract: The recent evidence-based shift towards an algorithm of early initiation and aggressive titration of insulin therapy in the management of type 2 diabetes requires the use of an effective insulin formulation that is both safe and acceptable to patients and physicians alike. The advent of the long-acting insulin analogues, insulin detemir and glargine, in the last decade has revolutionized insulin therapy in type 2 diabetes. Their unique pharmacokinetic and pharmacodynamic properties have offered tangible advantage over the conventional intermediate and long-acting insulin preparations in terms of improving glucose control as well as reducing risk of hypoglycemia and weight gain. This review focuses on the pharmacodynamic properties of the long-acting insulin analogue detemir, the outcome of studies on its relative efficacy and safety as well as its proposed place in the management of type 2 diabetes.Keywords: insulin detemir, type 2 diabetes, overweight
Tan, Shi-Xiong; Fisher-Wellman, Kelsey H.; Fazakerley, Daniel J.; Ng, Yvonne; Pant, Himani; Li, Jia; Meoli, Christopher C.; Coster, Adelle C. F.; Stöckli, Jacqueline; James, David E.
Aside from glucose metabolism, insulin regulates a variety of pathways in peripheral tissues. Under insulin-resistant conditions, it is well known that insulin-stimulated glucose uptake is impaired, and many studies attribute this to a defect in Akt signaling. Here we make use of several insulin resistance models, including insulin-resistant 3T3-L1 adipocytes and fat explants prepared from high fat-fed C57BL/6J and ob/ob mice, to comprehensively distinguish defective from unaffected aspects of insulin signaling and its downstream consequences in adipocytes. Defective regulation of glucose uptake was observed in all models of insulin resistance, whereas other major actions of insulin such as protein synthesis and anti-lipolysis were normal. This defect corresponded to a reduction in the maximum response to insulin. The pattern of change observed for phosphorylation in the Akt pathway was inconsistent with a simple defect at the level of Akt. The only Akt substrate that showed consistently reduced phosphorylation was the RabGAP AS160 that regulates GLUT4 translocation. We conclude that insulin resistance in adipose tissue is highly selective for glucose metabolism and likely involves a defect in one of the components regulating GLUT4 translocation to the cell surface in response to insulin. PMID:25720492
Full Text Available Insulin resistance is a condition of reduced biological response to insulin. Growing evidence indicates the role of the chronic low-grade inflammatory response in the pathogenesis of insulin resistance. Adipose tissue in obesity is characterized by increased lipolysis with the excessive release of free fatty acids, and is also a source of proinflammatory cytokines. Both these factors may inhibit insulin action. Proinflammatory cytokines exert their effect by stimulating major inflammatory NFκB and JNK pathways within the cells. Inflammatory processes in other insulin responsive tissues may also play a role in inducing insulin resistance. This paper is an overview of the chronic low-grade inflammation in adipose tissue, skeletal muscle, liver and endothelial cells during the development of insulin resistance.
. For the 2014 festival, the museum has entered into a collaboration with the Department for Performance Design at Roskilde University – with continued focus on sound and performance art, and social art in public spaces. With ACTS, art moves out of its usual exhibition space and instead utilizes the city, its...... various possibilities and public spaces as a stage. ACTS takes place in and around the museum and diverse locations in Roskilde city. ACTS is partly curated by the museum staff and partly by guest curators. ACTS 2014 is supported by Nordea-fonden and is a part of the project The Museum goes downtown.......Co-curator of ACTS 2014 together with Rasmus Holmboe, Judith Schwarzbart and Sanne Kofoed. ACTS is the Museum of Contemporary Art’s international bi-annual festival. ACTS was established in 2011 and, while the primary focus is on sound and performance art, it also looks toward socially oriented art...
Colombo, Natalia H; Shirakashi, Daisy J; Chiba, Fernando Y; Coutinho, Maria Sara de Lima; Ervolino, Edilson; Garbin, Cléa Adas Saliba; Machado, Ubiratan Fabres; Sumida, Doris H
The purpose of this study is to investigate whether local inflammatory events, such as periodontal disease, are able to increase tumor necrosis factor-alpha (TNF-α) plasmatic concentration and decrease insulin sensitivity and insulin signaling in non-diabetic rats. Forty-eight male Wistar rats (2 months old) were divided into two groups, with either ligature-induced periodontal disease (LPD) or control conditions (CN). Experiments were performed in both groups 28 days after ligature placement. Plasmatic concentration of glycemia and TNF-α (n = 10) were analyzed by the glucose oxidase and enzyme-linked immunosorbent assay method, respectively. Insulin sensitivity (n = 7) was measured using the insulin tolerance test. Insulin signal transduction (n = 7) was measured by pp185 tyrosine phosphorylation status in insulin-sensitive tissues using the Western blotting method. The LPD group showed decreased insulin sensitivity (P 0.05). TNF-α plasmatic concentration was higher in LPD rats compared to CN rats. In addition, a decrease in the pp185 tyrosine phosphorylation status was observed after insulin stimulus in both white adipose and skeletal muscle tissues of the LPD group compared with the CN group. LPD is able to cause alterations to both insulin signaling and insulin sensitivity, probably because of the elevation of TNF-α plasmatic concentration. Thus, the present results emphasize the importance of the prevention of local inflammatory diseases, such as periodontitis, to prevent diabetes mellitus.
Wang, Jiali; Liu, Baoshan; Han, Hui; Yuan, Qiuhuan; Xue, Mengyang; Xu, Feng; Chen, Yuguo
Although hyperglycemia is common in patients with acute myocardial infarction (MI), the underlying mechanisms are largely unknown. Insulin signaling plays a key role in the regulation of glucose homeostasis. In this study, we test the hypothesis that rapid alteration of insulin signaling pathways could be a potential contributor to acute hyperglycemia after MI. Male rats were used to produce MI by ligation of the left anterior descending coronary artery. Plasma glucose and insulin levels were significantly higher in MI rats than those in controls. Insulin-stimulated tyrosine phosphorylation of insulin receptor substrate 1 (IRS1) was reduced significantly in the liver tissue of MI rats compared with controls, followed by decreased attachment of phosphatidylinositol 3-kinase (PI3K) p85 subunit with IRS1 and Akt phosphorylation. However, insulin-stimulated signaling was not altered significantly in skeletal muscle after MI. The relative mRNA levels of phosphoenolpyruvate carboxykinase (PEPCK) and G6Pase were slightly higher in the liver tissue of MI rats than those in controls. Rosiglitazone (ROSI) markedly restored hepatic insulin signaling, inhibited gluconeogenesis and reduced plasma glucose levels in MI rats. Insulin resistance develops rapidly in liver but not skeletal muscle after MI, which contributes to acute hyperglycemia. Therapy aimed at potentiating hepatic insulin signaling may be beneficial for MI-induced hyperglycemia.
Holst, Jens Juul; Holland, William; Gromada, Jesper
In August 2016, several leaders in glucagon biology gathered for the European Association for the Study of Diabetes Hagedorn Workshop in Oxford, England. A key point of discussion focused on the need for basal insulin to allow for the therapeutic benefit of glucagon blockade in the treatment...... of diabetes. Among the most enlightening experimental results presented were findings from studies in which glucagon receptor-deficient mice were administered streptozotocin to destroy pancreatic β cells or had undergone diphtheria toxin-induced β cell ablation. This article summarizes key features...... of the discussion as a consensus was reached. Agents that antagonize glucagon may be of great benefit for the treatment of diabetes; however, sufficient levels of basal insulin are required for their therapeutic efficacy....
Pankov, Y A
Studies on experimental animals with knockout of the insulin receptor gene Insr (in the whole body or in certain tissues) and/or related genes encoding proteins involved in realization of insulin signal transduction in target cells, have made an important contribution to the elucidation of insulin regulation of metabolism, particularly fat metabolism. Since the whole insulin secreted by b-cells, together with the products of gastrointestinal tract digestion of proteins, fats, and carbohydrates reach the liver, the latter is the first organ on which this hormone acts. The liver employs released amino acids for synthesis of proteins, including apoproteins for various lipoproteins. Glucose is used for synthesis of glycogen, fatty acids, and triglycerides, which enter all the organs in very low density lipoproteins (VLDL). The LIRKO mice with knockout of the Insr gene in the liver demonstrated inhibition of synthesis of macromolecular compounds from amino acids, glucose, and fatty acids. Low molecular weight substances demonstrated increased entry to circulation, and together with other disorders induced hyperglycemia. In LIRKO mice blood glucose levels and glucose tolerance demonstrated time-dependent normalization and at later stages the increase in glucose levels was replaced by hypoglycemia. These changes can be well explained if we take into consideration that one of the main functions of insulin consists in stimulation of energy accumulation by means of activation of triglyceride deposition in adipose tissue. FIRKO mice with selective knockout of adipose tissue Insr were characterized by decreased uptake of glucose in adipocytes, and its transformation into lipids. However, the level of body fat in animals remained normal, possibly due to preserved insulin receptor in the liver and insulin-induced activation of triglyceride production which maintained normal levels of body fat stores, the effective functioning of adipose tissue and secretion of leptin by
Soares, Juliana Mikaelly Dias; Pereira Leal, Ana Ediléia Barbosa; Silva, Juliane Cabral; Almeida, Jackson R G S; de Oliveira, Helinando Pequeno
The development of alternatives for insulin secretion control in vivo or in vitro represents an important aspect to be investigated. In this direction, natural products have been progressively explored with this aim. In particular, flavonoids are potential candidates to act as insulin secretagogue. To study the influence of flavonoid on overall modulation mechanisms of insulin secretion. The research was conducted in the following databases and platforms: PubMed, Scopus, ISI Web of Knowledge, SciELO, LILACS, and ScienceDirect, and the MeSH terms used for the search were flavonoids, flavones, islets of Langerhans, and insulin-secreting cells. Twelve articles were included and represent the basis of discussion on mechanisms of insulin secretion of flavonoids. Papers in ISI Web of Knowledge were in number of 1, Scopus 44, PubMed 264, ScienceDirect 511, and no papers from LILACS and SciELO databases. According to the literature, the majority of flavonoid subclasses can modulate insulin secretion through several pathways, in an indication that corresponding molecule is a potential candidate for active materials to be applied in the treatment of diabetes. The action of natural products on insulin secretion represents an important investigation topic due to their importance in the diabetes controlIn addition to their typical antioxidant properties, flavonoids contribute to the insulin secretionThe modulation of insulin secretion is induced by flavonoids according to different mechanisms. Abbreviations used: KATP channels: ATP-sensitive K+ channels, GLUT4: Glucose transporter 4, ERK1/2: Extracellular signal-regulated protein kinases 1 and 2, L-VDCCs: L-type voltage-dependent Ca+2 channels, GLUT1: Glucose transporter 1, AMPK: Adenosine monophosphate-activated protein kinase, PTP1B: Protein tyrosine phosphatase 1B, GLUT2: Glucose transporter 2, cAMP: Cyclic adenosine monophosphate, PKA: Protein kinase A, PTK: Protein tyrosine kinase, CaMK II: Ca2+/calmodulin
Leutenegger, M; Gross, A; Ostermann, G; Grulet, H; Pasqual, C; Dijoux, B
The insulinorequiring diabetes is a notion which deserves a clear definition, essentially clinical, because it covers a wide range of physiopathological situations. The progressive degradation of Diabetes type II means a progressive discrepancy of insulinosecretion and above all an increase of insulinoresistance. The noxious part of chronical hyperglycemia is at present well known. The present therapeutical prospects tend to delay or limit insulinotherapy, by trying to obtain remission of insulinorequiring and some attempt to give a combined treatment associating insulin and hypoglycemic drugs.
Matteucci, Elena; Giampietro, Ottavio; Covolan, Vera; Giustarini, Daniela; Fanti, Paolo; Rossi, Ranieri
Insulin is a life-saving medication for people with type 1 diabetes, but traditional insulin replacement therapy is based on multiple daily subcutaneous injections or continuous subcutaneous pump-regulated infusion. Nonphysiologic delivery of subcutaneous insulin implies a rapid and sustained increase in systemic insulin levels due to the loss of concentration gradient between portal and systemic circulations. In fact, the liver degrades about half of the endogenous insulin secreted by the pancreas into the venous portal system. The reverse insulin distribution has short- and long-term effects on glucose metabolism. Thus, researchers have explored less-invasive administration routes based on innovative pharmaceutical formulations, which preserve hormone stability and ensure the therapeutic effectiveness. This review examines some of the recent proposals from clinical and material chemistry point of view, giving particular attention to patients’ (and diabetologists’) ideal requirements that organic chemistry could meet. PMID:26124635
Déat-Lainé, Emmanuelle; Hoffart, Valérie; Cardot, Jean-Michel; Subirade, Muriel; Beyssac, Eric
Insulin was encapsulated into microparticles (MP) made of denaturized whey proteins (WP) and alginate (ALG) using an extrusion/cold gelation process with calcium ions. High encapsulation efficiency of 85% was obtained. Influence of insulin on polymeric viscosity and on microparticle behavior was evaluated. Insulin seemed to interact with WP chains by non covalent binding and steric hindrance. This influence was balanced by ALG addition. Nevertheless, insulin was released rapidly by diffusion at both acidic and intestinal dissolution media. Despite this fast in vitro release, WP/ALG MP showed an important enzymatic inhibition effect on trypsin and alpha-chymotrypsin. Thus, WP/ALG MP contributed to an effective insulin protection towards enzymatic degradation. The aforementioned results suggested that WP based microparticles are a promising carrier for improving oral delivery of insulin. Copyright © 2012 Elsevier B.V. All rights reserved.
Tambascia, Marcos Antonio; Eliaschewitz, Freddy Goldberg
The development of extended-action insulin analogues was motivated by the unfavorable pharmacokinetic (PK) profile of the conventional long-acting insulin formulations, generally associated with marked inter and intra patient variability and site- and dose-dependent effect variation. The new ultra-long insulin analogue degludec (IDeg) has the same amino acid sequence as human insulin except for the removal of threonine in the position 30 of the B chain (Des-B30, "De") and the attachment, via a glutamic acid linker ("glu"), of a 16-carbon fatty diacid (hexadecanoic diacid, "dec") to lysine in the position 29 of the B chain. These modifications allow that, after changing from the pharmaceutical formulation to the subcutaneous environment, IDeg precipitates in the subcutaneous tissue, forming a depot that undergoes a highly predictable gradual dissociation. Thus, once-daily dosing of IDeg results in a low peak: trough ratio, with consequent low intra-individual variability and plasmatic concentrations less critically dependent upon the time of injections. The clinical development program of IDeg (BEGIN) was comprised of 9 therapeutic confirmatory trials of longer duration (26-52 weeks) and showed that the efficacy of IDeg is comparable to insulin glargine in type 1 (T1D) and type 2 (T2D) diabetes patients across different age, body mass index and ethnic groups. This new ultra-long insulin analogue presents as advantages flexibility in dose timing and lower risk of hypoglycemia.
Arkan, Melek C; Hevener, Andrea L; Greten, Florian R; Maeda, Shin; Li, Zhi-Wei; Long, Jeffrey M; Wynshaw-Boris, Anthony; Poli, Giuseppe; Olefsky, Jerrold; Karin, Michael
Inflammation may underlie the metabolic disorders of insulin resistance and type 2 diabetes. IkappaB kinase beta (IKK-beta, encoded by Ikbkb) is a central coordinator of inflammatory responses through activation of NF-kappaB. To understand the role of IKK-beta in insulin resistance, we used mice lacking this enzyme in hepatocytes (Ikbkb(Deltahep)) or myeloid cells (Ikbkb(Deltamye)). Ikbkb(Deltahep) mice retain liver insulin responsiveness, but develop insulin resistance in muscle and fat in response to high fat diet, obesity or aging. In contrast, Ikbkb(Deltamye) mice retain global insulin sensitivity and are protected from insulin resistance. Thus, IKK-beta acts locally in liver and systemically in myeloid cells, where NF-kappaB activation induces inflammatory mediators that cause insulin resistance. These findings demonstrate the importance of liver cell IKK-beta in hepatic insulin resistance and the central role of myeloid cells in development of systemic insulin resistance. We suggest that inhibition of IKK-beta, especially in myeloid cells, may be used to treat insulin resistance.
El Hage, Krystel; Pandyarajan, Vijay; Phillips, Nelson B; Smith, Brian J; Menting, John G; Whittaker, Jonathan; Lawrence, Michael C; Meuwly, Markus; Weiss, Michael A
Insulin, a protein critical for metabolic homeostasis, provides a classical model for protein design with application to human health. Recent efforts to improve its pharmaceutical formulation demonstrated that iodination of a conserved tyrosine (TyrB26) enhances key properties of a rapid-acting clinical analog. Moreover, the broad utility of halogens in medicinal chemistry has motivated the use of hybrid quantum- and molecular-mechanical methods to study proteins. Here, we (i) undertook quantitative atomistic simulations of 3-[iodo-TyrB26]insulin to predict its structural features, and (ii) tested these predictions by X-ray crystallography. Using an electrostatic model of the modified aromatic ring based on quantum chemistry, the calculations suggested that the analog, as a dimer and hexamer, exhibits subtle differences in aromatic-aromatic interactions at the dimer interface. Aromatic rings (TyrB16, PheB24, PheB25, 3-I-TyrB26, and their symmetry-related mates) at this interface adjust to enable packing of the hydrophobic iodine atoms within the core of each monomer. Strikingly, these features were observed in the crystal structure of a 3-[iodo-TyrB26]insulin analog (determined as an R6 zinc hexamer). Given that residues B24-B30 detach from the core on receptor binding, the environment of 3-I-TyrB26 in a receptor complex must differ from that in the free hormone. Based on the recent structure of a "micro-receptor" complex, we predict that 3-I-TyrB26 engages the receptor via directional halogen bonding and halogen-directed hydrogen bonding as follows: favorable electrostatic interactions exploiting, respectively, the halogen's electron-deficient σ-hole and electronegative equatorial band. Inspired by quantum chemistry and molecular dynamics, such "halogen engineering" promises to extend principles of medicinal chemistry to proteins. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.
Full Text Available Introduction: Diabetes mellitus is a common endocrine disease . The number of people with diabetes over the last twenty years has doubled . Asia as a result of rapid economic growth , as the center of the epidemic in the world . Iran is among the countries with a high prevalence of diabetes mellitus . Use of medicinal plants as adjunctive therapy along with medication always been original . In recent years the tendency of patients to alternative therapies and traditional medicine has increased. Methods : Among patients referred to clinics of University of Medical Sciences, Yazd, Iran , 67 people were selected and randomly divided into two groups,intervention or placebo. Patients in the intervention group received 3 tablets of 300 mg bee propolis and in the control group received placebo . The study lasted 12 weeks . Serum insulin and insulin resistance index were evaluated at the beginning and end of the study. Results: 57 patients completed the study . The average demographic characteristics , anthropometric indices , serum insulin and insulin resistance index at the beginning and end of the study between the two groups showed no significant difference. Conclusion : In this study , supplementation with bee propolis for 12 weeks , on the serum insulin and indices of insulin resistance in patients with type II diabetes is not effective . Further studies are needed to make a final decision.
Full Text Available Abstract Background Anaesthesia is commonly employed prior to surgical investigations and to permit icv injections in rodents. Indeed it is standard practise in many studies examining the subsequent actions of hormones and growth factors on the brain. Recent evidence that the basal activity of specific intracellular signalling proteins can be affected by anaesthesia prompted us to examine the effect of anaesthesia not only on the basal activity but also the insulin sensitivity of the major insulin signalling pathways. Results We find that urethane- and ketamine-induced anaesthesia results in rapid activation of the phosphatidylinositol (PI 3-kinase-protein kinase B (PKB signalling pathway in the brain, increases tau phosphorylation while at the same time reducing basal activity of the Ras-ERK pathway. Subsequent injection of insulin does not alter the activity of either the PI 3-kinase or ERK signalling pathways, indicating a degree of neuronal molecular insulin resistance. However, if body temperature is maintained during anaesthesia then there is no alteration in the basal activity of these signalling molecules. Subsequent response of both pathways to insulin injection is restored. Conclusion The data is consistent with a hypothermia related alteration in neuronal signalling following anaesthesia, and emphasises the importance of maintaining the body temperature of rodents when monitoring insulin (or growth factor/neurotrophic agent action in the brain of anesthetised rodents.
Gupta, Jyoti; Felner, Eric I; Prausnitz, Mark R
Microneedles have previously been used to deliver insulin to animal models, but not in human subjects. This study tested the hypothesis that hollow microneedles can deliver insulin to modulate blood glucose levels in subjects with type 1 diabetes in a minimally invasive manner. This study was carried out in two adults with type 1 diabetes and evaluated bolus delivery of lispro insulin using a hollow microneedle compared to a catheter infusion set (9 mm). The study first determined the minimum insulin delivery depth by administering insulin from microneedles inserted 1, 3.5, and 5 mm into the skin of fasting subjects and then assessed the efficacy of insulin delivery from microneedles inserted 1 mm into the skin to reduce postprandial glucose levels. Blood samples were periodically assayed for plasma free insulin and plasma glucose levels for up to 3.5 h. The first phase of the study indicated that microneedles inserted at the shallowest depth of 1 mm within the skin led to rapid insulin absorption and reduction in glucose levels. Bolus insulin delivery followed by consumption of a standardized meal in the second phase revealed that microneedles were effective in reducing postprandial glucose levels. Subjects reported no pain from microneedle treatments, and there were no adverse events. This study provides the first proof of concept that hollow microneedles can effectively deliver bolus insulin to type 1 diabetes subjects in a minimally invasive manner.
A prospective randomised cross-over study of the effect of insulin analogues and human insulin on the frequency of severe hypoglycaemia in patients with type 1 diabetes and recurrent hypoglycaemia (the HypoAna trial: study rationale and design
Full Text Available Abstract Background Severe hypoglycaemia still represents a significant problem in insulin-treated diabetes. Most patients do not experience severe hypoglycaemia often. However, 20% of patients with type 1 diabetes experience recurrent severe hypoglycaemia corresponding to at least two episodes per year. The effect of insulin analogues on glycaemic control has been documented in large trials, while their effect on the frequency of severe hypoglycaemia is less clear, especially in patients with recurrent severe hypoglycaemia. The HypoAna Trial is designed to investigate whether short-acting and long-acting insulin analogues in comparison with human insulin are superior in reducing the occurrence of severe hypoglycaemic episodes in patients with recurrent hypoglycaemia. This paper reports the study design of the HypoAna Trial. Methods/design The study is a Danish two-year investigator-initiated, prospective, randomised, open, blinded endpoint (PROBE, multicentre, cross-over trial investigating the effect of insulin analogues versus human insulin on the frequency of severe hypoglycaemia in subjects with type 1 diabetes. Patients are randomised to treatment with basal-bolus therapy with insulin detemir / insulin aspart or human NPH insulin / human regular insulin in random order. The major inclusion criterion is history of two or more episodes of severe hypoglycaemia in the preceding year. Discussion In contrast to almost all other studies in this field the HypoAna Trial includes only patients with major problems with hypoglycaemia. The HypoAna Trial will elucidate whether basal-bolus regimen with short-acting and long-acting insulin analogues in comparison with human insulin are superior in reducing occurrence of severe hypoglycaemic episodes in hypoglycaemia prone patients with type 1 diabetes. http://www.clinicaltrials.gov: NCT00346996.
ter Horst, K. W.; Gilijamse, P. W.; Koopman, K. E.; de Weijer, B. A.; Brands, M.; Kootte, R. S.; Romijn, J. A.; Ackermans, M. T.; Nieuwdorp, M.; Soeters, M. R.; Serlie, M. J.
Insulin resistance is the major contributor to cardiometabolic complications of obesity. We aimed to (1) establish cutoff points for insulin resistance from euglycemic hyperinsulinemic clamps (EHCs), (2) identify insulin-resistant obese subjects and (3) predict insulin resistance from routinely
Monzo, Hector J.; Coppieters, Natacha [Centre for Brain Research, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag, 92019, Auckland (New Zealand); Department of Anatomy and Medical Imaging, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag, 92019, Auckland (New Zealand); Park, Thomas I.H. [Centre for Brain Research, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag, 92019, Auckland (New Zealand); Department of Pharmacology, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag, 92019, Auckland (New Zealand); Dieriks, Birger V.; Faull, Richard L.M. [Centre for Brain Research, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag, 92019, Auckland (New Zealand); Department of Anatomy and Medical Imaging, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag, 92019, Auckland (New Zealand); Dragunow, Mike [Centre for Brain Research, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag, 92019, Auckland (New Zealand); Department of Pharmacology, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag, 92019, Auckland (New Zealand); Curtis, Maurice A., E-mail: firstname.lastname@example.org [Centre for Brain Research, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag, 92019, Auckland (New Zealand); Department of Anatomy and Medical Imaging, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag, 92019, Auckland (New Zealand)
Cellular interactions with the extracellular environment are modulated by cell surface polysialic acid (PSA) carried by the neural cell adhesion molecule (NCAM). PSA-NCAM is involved in cellular processes such as differentiation, plasticity, and migration, and is elevated in Alzheimer's disease as well as in metastatic tumour cells. Our previous work demonstrated that insulin enhances the abundance of cell surface PSA by inhibiting PSA-NCAM endocytosis. In the present study we have identified a mechanism for insulin-dependent inhibition of PSA-NCAM turnover affecting cell migration. Insulin enhanced the phosphorylation of the focal adhesion kinase leading to dissociation of αv-integrin/PSA-NCAM clusters, and promoted cell migration. Our results show that αv-integrin plays a key role in the PSA-NCAM turnover process. αv-integrin knockdown stopped PSA-NCAM from being endocytosed, and αv-integrin/PSA-NCAM clusters co-labelled intracellularly with Rab5, altogether indicating a role for αv-integrin as a carrier for PSA-NCAM during internalisation. Furthermore, inhibition of p-FAK caused dissociation of αv-integrin/PSA-NCAM clusters and counteracted the insulin-induced accumulation of PSA at the cell surface and cell migration was impaired. Our data reveal a functional association between the insulin/p-FAK-dependent regulation of PSA-NCAM turnover and cell migration through the extracellular matrix. Most importantly, they identify a novel mechanism for insulin-stimulated cell migration. - Highlights: • Insulin modulates PSA-NCAM turnover through upregulation of p-FAK. • P-FAK modulates αv-integrin/PSA-NCAM clustering. • αv-integrin acts as a carrier for PSA-NCAM endocytosis. • Cell migration is promoted by cell surface PSA. • Insulin promotes PSA-dependent migration in vitro.
Vinther, Tine N; Pettersson, Ingrid; Huus, Kasper
The structure of insulin, a glucose homeostasis-controlling hormone, is highly conserved in all vertebrates and stabilized by three disulfide bonds. Recently, we designed a novel insulin analogue containing a fourth disulfide bond located between positions A10-B4. The N-terminus of insulin's B......-chain is flexible and can adapt multiple conformations. We examined how well disulfide bond predictions algorithms could identify disulfide bonds in this region of insulin. In order to identify stable insulin analogues with additional disulfide bonds, which could be expressed, the Cβ cut-off distance had...... in comparison to analogues with additional disulfide bonds that were more difficult to predict. In contrast, addition of the fourth disulfide bond rendered all analogues resistant to fibrillation under stress conditions and all stable analogues bound to the insulin receptor with picomolar affinities. Thus...
Bornfeldt, Karin E.; Tabas, Ira
Progress in preventing atherosclerotic coronary artery disease (CAD) has been stalled by the epidemic of type 2 diabetes. Further advances in this area demand a thorough understanding of how two major features of type 2 diabetes, insulin resistance and hyperglycemia, impact atherosclerosis. Insulin resistance is associated with systemic CAD risk factors, but increasing evidence suggests that defective insulin signaling in atherosclerotic lesional cells also plays an important role. The role o...
Ahmad, Munir; Gardner, QurratulAnn Afza; Rashid, Naeem; Akhtar, Muhammad
Eight proinsulin encoding genes were prepared and their translation products, when treated with a cocktail of trypsin and carboxypeptidase B, analyzed for the following features. One, their ability to undergo facile removal of the N-terminal linker, generating the phenylalanine residue destined to be the N-terminal of the B-chain of insulin, at a rate similar to that involved in the removal of the C-peptide. Two, processing of diarginyl insulin, produced in the latter process, by carboxypeptidase B then needed to be rapid to remove the two arginine residues, Three, both these operations were to be efficient whether the N-terminal methionine was acylated or not. Four, the proinsulin constructs needed to contain a minimum number of sites for acylation. The aforementioned features were monitored by mass spectrometry and the proinsulin derivative containing MRR at the N-terminal and K 64 mutated to Q 64 , designated as MRR-(Q 64 ) human proinsulin [MRR-(Q 64 ) hpi] optimally fulfilled these requirements. The derivative was smoothly acylated with reagents of two chain lengths (acetyl and dodecanoyl) to give acetyl/dodecanoyl MRR-(Q 64 ) hpi. Acetyl MRR-(Q 64 ) hpi, using the cocktail of the two enzymes, was smoothly converted into, acetyl insulin. However, when dodecanoyl MRR-(Q 64 ) hpi was processed with the above cocktail, carboxypeptidase B (whether from animal pancreas or recombinant) showed an unexpected specificity of acting on the K 29 -T 30 bond of the insulin derivatives when K 29 contained a large hydrophobic acyl group, generating dodecanoyl des-30 insulin. Copyright © 2017 Elsevier Inc. All rights reserved.
Varshosaz, Jaleh; Sadrai, Hassan; Heidari, Alireza
Recently nasal delivery of insulin has gained considerable attention. Some limitations of this route include rapid mucociliary clearance of the drug from the site of deposition resulting in short time span available for absorption and low permeability of the nasal membrane for peptides. The objective of the present study was development of a chitosan bioadhesive gel for nasal delivery of insulin. A nasal perfusion test was used to study the toxicity of 4 absorption enhancers: saponin, sodium deoxycholate, ethylendiamine tetra-Acetic Acid (EDTA) and lecithin. The gels contained 4,000 Iu/dl insulin, 2 or 4% of low and medium molecular weight of chitosan, and lecithin or EDTA. Drug release was studied by a membraneless diffusion method and bioadhesion by a modified tensiometry test. The optimized gel was administered nasally in diabetic rats. The serum insulin levels were analyzed by an insulin enzyme immunoassay kit and serum glucose by glucose oxidase method kits. Formulations containing 2% of low molecular weight of chitosan with EDTA had higher release percentage and dissolution efficiency (DE)(2.5%), lower T(50%) (Time required to release 50% of the drug), mean dissolution time, and bioadhesion than gels containing 4% of medium molecular weight of chitosan with lecithin. Insulin was released by a zero-order kinetic from the gels. The gel of 2% medium molecular weight of chitosan with EDTA caused increase in insulin absorption and reduction the glucose level by as much as 46% of the intravenous route. Considering our in vitro and in vivo studies, the proposed gel formulation could be a useful preparation for controlled delivery of insulin through the nasal route.
Gonzalez-Franquesa, Alba; Patti, Mary-Elizabeth
Insulin resistance precedes and predicts the onset of type 2 diabetes (T2D) in susceptible humans, underscoring its important role in the complex pathogenesis of this disease. Insulin resistance contributes to multiple tissue defects characteristic of T2D, including reduced insulin-stimulated glucose uptake in insulin-sensitive tissues, increased hepatic glucose production, increased lipolysis in adipose tissue, and altered insulin secretion. Studies of individuals with insulin resistance, both with established T2D and high-risk individuals, have consistently demonstrated a diverse array of defects in mitochondrial function (i.e., bioenergetics, biogenesis and dynamics). However, it remains uncertain whether mitochondrial dysfunction is primary (critical initiating defect) or secondary to the subtle derangements in glucose metabolism, insulin resistance, and defective insulin secretion present early in the course of disease development. In this chapter, we will present the evidence linking mitochondrial dysfunction and insulin resistance, and review the potential for mitochondrial targets as a therapeutic approach for T2D.
Gonzalez-Franquesa, Alba; Patti, Mary-Elizabeth
Insulin resistance precedes and predicts the onset of type 2 diabetes (T2D) in susceptible humans, underscoring its important role in the complex pathogenesis of this disease. Insulin resistance contributes to multiple tissue defects characteristic of T2D, including reduced insulin-stimulated glu......Insulin resistance precedes and predicts the onset of type 2 diabetes (T2D) in susceptible humans, underscoring its important role in the complex pathogenesis of this disease. Insulin resistance contributes to multiple tissue defects characteristic of T2D, including reduced insulin...... of defects in mitochondrial function (i.e., bioenergetics, biogenesis and dynamics). However, it remains uncertain whether mitochondrial dysfunction is primary (critical initiating defect) or secondary to the subtle derangements in glucose metabolism, insulin resistance, and defective insulin secretion...... present early in the course of disease development. In this chapter, we will present the evidence linking mitochondrial dysfunction and insulin resistance, and review the potential for mitochondrial targets as a therapeutic approach for T2D....
Full Text Available Objective: To compare the treatment costs of insulin glargine (IG; Lantus® to detemir (ID; Levemir®, both combined with bolus insulin aspart (NovoRapid® in type 2 diabetes (T2D in Germany. Methods: Cost comparison was based on data of a 1-year randomised controlled trial . IG was administered once daily and ID once (57% of patients or twice daily (43% according to treatment response. At the end of the trial, mean daily basal insulin doses were 0.59 U/kg (IG and 0.82 U/kg (ID. Aspart doses were 0.32 U/kg (IG and 0.36 U/kg (ID. Costs were calculated from the German statutory health insurance (SHI perspective using official 2008 prices. Sensitivity analyses were performed to test robustness of the results. Results: Annual basal and bolus insulin costs per patient were € 1,473 (IG and € 1,940 (ID. The cost of lancets and blood glucose test strips were € 1,125 (IG and € 1,286 (ID. Annual costs for needles were € 393 (IG and € 449 (ID. The total annual cost per patient of administering IG was € 2,991 compared with € 3,675 for ID, translating into a 19% annual cost difference of € 684/patient. Base case results were robust to varying assumptions for insulin dose, insulin price, change in weight and proportion of ID once daily administrations. Conclusion: IG and ID basal-bolus regimes have comparative safety and efficacy, based on the Hollander study, IG however may represent a significantly more cost saving option for T2D patients in Germany requiring basal-bolus insulin analogue therapy with potential annual cost savings of € 684/patient compared to ID.
Shuai Wang; Wei Wei; Yadong Zheng; Junling Hou; Yongxi Dou; Shaohua Zhang; Xuenong Luo; Xuepeng Cai
As the linker between the A chain and B chain of proinsulin, C-peptide displays high variability in length and amino acid composition, and has been considered as an inert byproduct of insulin synthesis and processing for many years. Recent studies have suggested that C-peptide can act as a bioactive hormone, exerting various biological effects on the pathophysiology and treatment of diabetes. In this study, we analyzed the coevolution of insulin molecules among vertebrates, aiming at explorin...
Nelson L. Moreno-Ruíz
Full Text Available Potassium is the main intracellular cation and determines potential cell rest. Hypercaliemia is thus frequently, but not always, associated with severe renal failure. It is a potentially fatal entity due to its ability to produce arrhythmias. Several therapeutic options are intended to stabilize the membrane and redistribute potassium to the cell in acute treatment whilst a patient is undergoing dialysis. Insulin is given in such treatment as it rapidly lowers potassium levels, even though such reduction is transitory. Nevertheless, insulin may be given in several ways depending on the school of formation, availability of resources and a doctor's particular knowledge.
GLUT-4 is the major facilitative glucose transporter isoform in tissues that exhibit insulin-stimulated glucose transport. Insulin regulates glucose transport by the rapid translocation of GLUT-4 from an intracellular compartment to the plasma membrane. A critical feature of this process is the efficient exclusion of GLUT-4 from the plasma membrane in the absence of insulin. To identify the amino acid domains of GLUT-4 which confer intracellular sequestration, we analyzed the subcellular dist...
Hou, Zhenqing; Zhang, Zhenxi; Wu, Hong
Sanguis draxonis (SD) is a Chinese traditional herb that is prescribed for the handling of diabetic disorders. In this study, the effects of an oral administration of SD at dosages of 100, 300, and 500 mg kg(-1) once a day, respectively, on the formation of insulin resistance were investigated in vivo in two models of insulin-resistant rats, HFD rats (high-fat diet-induced insulin-resistant rats) and IILI rats (induced by the intraperitoneal injections of long-acting insulin at dosage of 0.5 U kg(-1) three times daily). The insulin resistance was indicated using the loss of tolbutamide-induced hypoglycemic activity. After the oral administration of SD (300 and 500 mg kg(-1) once a day for 7 days) to HFD rats, both plasma glucose and insulin concentration were decreased significantly, while the hypoglycemic activity of tolbutamide (10 mg kg(-1), i.p.) was significantly enhanced as compared with that of the vehicle-treatment (0.9% saline solution used as vehicle to disperse SD, w/v). Moreover, the formation of insulin resistance in IILI rats had been improved significantly with SD treatment (100, 300, 500 mg kg(-1) once a day for 14 days), but the influence of SD treatment on both plasma glucose and insulin concentration was not observed. For STZ-induced diabetic rats, the action of SD (300 and 500 mg kg(-1) once a day for 14 days) showed more effective on an increase of response to the exogenous short-acting porcine insulin than that of the metformin administrated orally at dosage of 320 mg kg(-1) three times daily. The present studies suggest that an oral administration of SD can increase insulin sensitivity and improve the development of insulin resistance in rats.
Soeters, Maarten R.; Soeters, Peter B.
Insulin resistance is perceived as deleterious, associated with conditions as the metabolic syndrome, type 2 diabetes mellitus and critical illness. However, insulin resistance is evolutionarily well preserved and its persistence suggests that it benefits survival. Insulin resistance is important in
Full Text Available It is estimated that 5-10% of women of reproductive age have polycystic ovarian syndrome (PCOS. While insulin resistance is not part of the diagnostic criteria for PCOS, its importance in the pathogenesis of PCOS cannot be denied. PCOS is associated with insulin resistance independent of total or fat-free body mass. Post-receptor defects in the action of insulin have been described in PCOS which are similar to those found in obesity and type 2 diabetes. Treatment with insulin sensitizers, metformin and thiazolidinediones, improve both metabolic and hormonal patterns and also improve ovulation in PCOS. Recent studies have shown that PCOS women have higher circulating levels of inflammatory mediators like C-reactive protein, tumour necrosis factor- , tissue plasminogen activator and plasminogen activator inhibitor-1 (PAI-1 . It is possible that the beneficial effect of insulin sensitizers in PCOS may be partly due to a decrease in inflammation.
Goustin, Anton-Scott; Abou-Samra, Abdul B
Ahsg (fetuin-A) is a 55-59kDa phosphorylated glycoprotein synthesized in the adult predominantly by hepatocytes, from which it enters the circulation. When dysregulated, this glycoprotein operates to influence the clinical sequelae of insulin resistance-type 2 diabetes and cardiovascular disease. The pathological sequelae likely arise from two separable molecular "faces" of Ahsg-one acting at the level of the insulin receptor and a second face influencing ectopic biomineralization in the intima. A detailed understanding of these two functional faces of Ahsg is not yet clear for lack of structural studies. Ahsg has a physiological role in the biomineralization of bone, which when dysregulated can lead to ectopic calcification of soft tissues in the vasculature. Ahsg has a second physiological function in regulating how insulin signals through its receptor, a transmembrane tyrosine kinase. Dysregulation of this "face" of Ahsg results in morbid sequelae such as impaired glucose disposal and fatty liver. Ahsg binds to tandem fibronectin type 3 (Fn3) domains present in the 194 amino acid residue extracellular portion of the β-subunit of the insulin receptor, distant from the high-affinity pocket formed by two complementing α-subunits where insulin binds. Only two proteins are known to bind directly to the insulin receptor ectodomain - insulin and Ahsg - the former turns on the receptor's intrinsic tyrosine kinase (TK) activity, and the latter shuts it down. Recent X-ray crystallographic studies of the ectodomain of the insulin receptor now sharpen our understanding of the receptor's extracellular α-subunit and linked β-subunit. Ahsg genotype and its circulating level have been correlated with body morphometrics (obese versus lean and visceral adiposity) in epidemiological studies enrolling thousands of patients. Epidemiological studies from the clinic reveal high levels of circulating Ahsg in insulin resistance and diabetes. This review endeavors to explain how one
... Current Issue Past Issues Special Section: Focus on Communication Balancing Acts Past Issues / Fall 2008 Table of ... It was like watching a movie, but every couple of frames were skipping. It was disorienting," the ...
Bhutani, Garima; Kalra, Sanjay
The study is aimed to assess whether the information contained in standard pharmacology, endocrinology, and diabetology textbooks regarding timings of administration, frequency and dose of various insulins is adequate and also to see whether the information contained in these texts is concordant with product inserts. Four standard textbooks of pharmacology, two of diabetology and three of endocrinology were assessed for the published information regarding dose, timing, and frequency of insulin administration. The product inserts of commonly available insulins in India were also studied for the same. Various omissions and disparities could be seen in the coverage of insulins in standard textbooks. Posology information about premixed insulins and basal insulins have been omitted by the majority of the textbooks. Details about dose, frequency and timings of ultra-short acting insulins have also not been covered by all textbooks. Some discrepancies regarding prescribing information was also noted in product inserts, especially in case of newer insulins. Thus, this article stresses upon the need of a uniform source of information for providing adequate and standardized knowledge regarding timing, frequency, and dose of insulins.
Hultström, Michael; Roxhed, Niclas
The incidence of insulinopenic diabetes mellitus is constantly increasing, and in addition, approximately a third of all hyperinsulinemic diabetic patients develop insulinopenia. Optimal glycemic control is essential to minimize the risk for diabetes-induced complications, but the majority of diabetic patients fail to achieve proper long-term glucose levels even in clinical trials, and even more so in clinical practice. Compliance with a treatment regimen is likely to be higher if the procedure is simple, painless, and discreet. Thus, insulin has been suggested for nasal, gastrointestinal, and inhalation therapy, but so far with considerable downsides in effect, side effects, or patient acceptance. The stratum corneum is the main barrier preventing convenient drug administration without the drawbacks of subcutaneous injections. Recently, devices with miniaturized needles have been developed that combine the simplicity and discretion of patch-based treatments, but with the potential of peptide and protein administration. As this review describes, initial comparisons with subcutaneous administration now suggest microneedle patches for active insulin delivery are efficient in maintaining glycemic control. Hollow microneedle technology could also prove to be efficient in systemic as well as local delivery of other macromolecular drugs, such as vaccines. PMID:24876605
Riehle, Christian; Abel, E. Dale
Heart failure is associated with generalized insulin resistance. Moreover, insulin resistant states such as type 2 diabetes and obesity increases the risk of heart failure even after adjusting for traditional risk factors. Insulin resistance or type 2 diabetes alters the systemic and neurohumoral milieu leading to changes in metabolism and signaling pathways in the heart that may contribute to myocardial dysfunction. In addition, changes in insulin signaling within cardiomyocytes develop in the failing heart. The changes range from activation of proximal insulin signaling pathways that may contribute to adverse left ventricular remodeling and mitochondrial dysfunction to repression of distal elements of insulin signaling pathways such as forkhead (FOXO) transcriptional signaling or glucose transport which may also impair cardiac metabolism, structure and function. This article will review the complexities of insulin signaling within the myocardium and ways in which these pathways are altered in heart failure or in conditions associated with generalized insulin resistance. The implications of these changes for therapeutic approaches to treating or preventing heart failure will be discussed. PMID:27034277
Younk, Lisa M; Lamos, Elizabeth M; Davis, Stephen N
Cardiovascular disease remains one of the leading causes of morbidity and mortality in diabetes mellitus. A causal link between insulin, atherosclerosis and cardiovascular risk has been investigated at the basic science level and studied in large clinical trials. The cardiovascular actions of insulin and its role at the level of the endothelium will be reviewed. Cardiovascular outcomes in several large diabetes trials where insulin management was prominent will be summarized. The vascular actions of insulin are complex and mediated primarily via nitric oxide and endothelin-1. It appears that insulin resistance, rather than hyperinsulinemia itself, increases cardiovascular risk. In fact, hyperinsulinemia in the setting of normal beta cell function protects obese and insulin-resistant individuals from type 2 diabetes. Large clinical trials have supported that insulin management is not associated with increased adverse outcomes. A multifactorial approach targeting modifiable risk factors, including smoking cessation, blood pressure and lipid management, reduces cardiovascular risk. Therapy goals should be individualized and hypoglycemia, especially in individuals receiving insulin management, should be strictly avoided.
Javelin, a Lone Peak Engineering Inc. Company has introduced the SteamRoller(TM) System as a commercial product. The system was designed by Javelin during a Phase II NASA funded small commercial product. The purpose of the invention was to allow automated-feed of flexible ceramic tapes to the Laminated Object Manufacturing rapid prototyping equipment. The ceramic material that Javelin was working with during the Phase II project is silicon nitride. This engineered ceramic material is of interest for space-based component.
Hänzelmann, Sonja; Wang, Jinling; Güney, Emre; Tang, Yunzhao; Zhang, Enming; Axelsson, Annika S; Nenonen, Hannah; Salehi, Albert S; Wollheim, Claes B; Zetterberg, Eva; Berntorp, Erik; Costa, Ivan G; Castelo, Robert; Rosengren, Anders H
The disease mechanisms underlying type 2 diabetes (T2D) remain poorly defined. Here we aimed to explore the pathophysiology of T2D by analyzing gene co-expression networks in human islets. Using partial correlation networks we identified a group of co-expressed genes ('module') including F2RL2 that was associated with glycated hemoglobin. F2Rl2 is a G-protein-coupled receptor (GPCR) that encodes protease-activated receptor-3 (PAR3). PAR3 is cleaved by thrombin, which exposes a 6-amino acid sequence that acts as a 'tethered ligand' to regulate cellular signaling. We have characterized the effect of PAR3 activation on insulin secretion by static insulin secretion measurements, capacitance measurements, studies of diabetic animal models and patient samples. We demonstrate that thrombin stimulates insulin secretion, an effect that was prevented by an antibody that blocks the thrombin cleavage site of PAR3. Treatment with a peptide corresponding to the PAR3 tethered ligand stimulated islet insulin secretion and single β-cell exocytosis by a mechanism that involves activation of phospholipase C and Ca(2+) release from intracellular stores. Moreover, we observed that the expression of tissue factor, which regulates thrombin generation, was increased in human islets from T2D donors and associated with enhanced β-cell exocytosis. Finally, we demonstrate that thrombin generation potential in patients with T2D was associated with increased fasting insulin and insulinogenic index. The findings provide a previously unrecognized link between hypercoagulability and hyperinsulinemia and suggest that reducing thrombin activity or blocking PAR3 cleavage could potentially counteract the exaggerated insulin secretion that drives insulin resistance and β-cell exhaustion in T2D.
During the first two decades of the 20th century, several investigators prepared extracts of pancreas that were often successful in lowering blood sugar and reducing glycosuria in test animals. However, they were unable to remove impurities, and toxic reactions prevented its use in humans with diabetes. In the spring of 1921, Frederick G. Banting, a young Ontario orthopedic surgeon, was given laboratory space by J.J.R. Macleod, the head of physiology at the University of Toronto, to investigate the function of the pancreatic islets. A student assistant, Charles Best, and an allotment of dogs were provided to test Banting's hypothesis that ligation of the pancreatic ducts before extraction of the pancreas, destroys the enzyme-secreting parts, whereas the islets of Langerhans, which were believed to produce an internal secretion regulating sugar metabolism, remained intact. He believed that earlier failures were attributable to the destructive action of trypsin. The name "insuline" had been introduced in 1909 for this hypothetic substance. Their experiments produced an extract of pancreas that reduced the hyperglycemia and glycosuria in dogs made diabetic by the removal of their pancreases. They next developed a procedure for extraction from the entire pancreas without the need for duct ligation. This extract, now made from whole beef pancreas, was successful for treating humans with diabetes. Facilitating their success was a development in clinical chemistry that allowed blood sugar to be frequently and accurately determined in small volumes of blood. Success with purification was largely the work of J.B. Collip. Yield and standardization were improved by cooperation with Eli Lilly and Company. When the Nobel Prize was awarded to Banting and Macleod for the discovery of insulin, it aggravated the contentious relationship that had developed between them during the course of the investigation. Banting was outraged that Macleod and not Best had been selected, and he
Vos, Rimke C; van Avendonk, Mariëlle Jp; Jansen, Hanneke; Goudswaard, Alexander N; van den Donk, Maureen; Gorter, Kees; Kerssen, Anneloes; Rutten, Guy Ehm
It is unclear whether people with type 2 diabetes mellitus on insulin monotherapy who do not achieve adequate glycaemic control should continue insulin as monotherapy or can benefit from adding oral glucose-lowering agents to the insulin therapy. To assess the effects of insulin monotherapy compared with the addition of oral glucose-lowering agents to insulin monotherapy for people with type 2 diabetes already on insulin therapy and inadequate glycaemic control. We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, ClinicalTrials.gov, the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) and reference lists of articles. The date of the last search was November 2015 for all databases. Randomised controlled clinical trials of at least two months' duration comparing insulin monotherapy with combinations of insulin with one or more oral glucose-lowering agent in people with type 2 diabetes. Two review authors independently selected trials, assessed risk of bias, extracted data and evaluated overall quality of the evidence using GRADE. We summarised data statistically if they were available, sufficiently similar and of sufficient quality. We performed statistical analyses according to the statistical guidelines in the Cochrane Handbook for Systematic Reviews of Interventions. We included 37 trials with 40 treatment comparisons involving 3227 participants. The duration of the interventions ranged from 2 to 12 months for parallel trials and two to four months for cross-over trials.The majority of trials had an unclear risk of bias in several risk of bias domains. Fourteen trials showed a high risk of bias, mainly for performance and detection bias. Insulin monotherapy, including once-daily long-acting, once-daily intermediate-acting, twice-daily premixed insulin, and basal-bolus regimens (multiple injections), was compared to insulin in combination with sulphonylureas (17 comparisons: glibenclamide
Lau, Ip Tim; Lee, Ka Fai; So, Wing Yee; Tan, Kathryn; Yeung, Vincent Tok Fai
To review published clinical studies on the efficacy and safety of new insulin glargine 300 units/mL (Gla-300), a new long-acting insulin analog, for the treatment of type 1 and type 2 diabetes mellitus (T1DM, T2DM). Data sources comprised primary research articles on Gla-300, including pharmacodynamic, pharmacokinetic, and clinical studies. In pharmacodynamic and pharmacokinetic studies, Gla-300 showed a flatter time-action profile and longer duration of action than Gla-100. Noninferiority of Gla-300 versus Gla-100 for lowering of glycated hemoglobin was demonstrated in Phase III clinical studies covering a range of T1DM and T2DM patient populations. Over 6-12 months of follow-up, Gla-300 consistently showed comparable glycemic efficacy with less hypoglycemia vs Gla-100, even during the first 8 weeks of treatment. Although titrated insulin doses were 11%-17% higher with Gla-300 vs Gla-100, changes in body weight were similar or favored Gla-300. Clinical studies provide evidence that the pharmacodynamic and pharmacokinetic properties of Gla-300 may translate into clinical benefits in both T1DM and T2DM. Gla-300 may provide a new option for people initiating basal insulin, those requiring higher basal insulin doses, those with T1DM, and those who may be at increased risk for hypoglycemia, such as people with chronic kidney disease, the elderly, and those with cardiovascular comorbidities.
Coomans, C.P.; Biermasz, N.R.; Geerling, J.J.; Guigas, B.; Rensen, P.C.N.; Havekes, L.M.; Romijn, J.A.
OBJECTIVE - Insulin inhibits endogenous glucose production (EGP) and stimulates glucose uptake in peripheral tissues. Hypothalamic insulin signaling is required for the inhibitory effects of insulin on EGP. We examined the contribution of central insulin signaling on circulating insulin-stimulated
Zemel, M B
Hypertension in obesity and insulin resistance has been attributed to insulin stimulation of sympathetic neural output and renal sodium retention. However, recent data demonstrates a significant vasodilatory effect of insulin and suggests that vascular smooth muscle resistance to this action may instead be the cause of hypertension in insulin resistance. This concept is supported by the observation that pharmacological amplification of peripheral insulin sensitivity results in reduced arterial pressure. Insulin attenuates vasoconstrictor responses to pressor agonists and accelerates vascular smooth muscle relaxation, while these effects are blunted in obesity and insulin resistance. Insulin regulation of vasoconstriction and vascular relaxation appears to be secondary to regulation of intracellular Ca2+ ([Ca2+]i), as insulin attenuates both voltage- and receptor-mediated Ca2+ influx and stimulates both the transcription and activity of Ca(2+)-ATPase in vascular smooth muscle cells. Further, these effects are also blunted in insulin resistance. Although [Ca2+]i plays a poorly understood role in insulin signalling, increases beyond an optimal range results in impaired insulin sensitivity, possibly by Ca(2+)-inhibition of insulin-induced dephosphorylation of insulin-sensitive substrates. Consistent with this concept, ectopic overexpression of the agouti gene in the viable yellow (Avy) mouse results in increased skeletal myocyte [Ca2+]i. Accordingly, increased [Ca2+]i in primary insulin target tissues appears to result in peripheral insulin resistance which then results in aberrant regulation of vascular smooth muscle [Ca2+]i and increases in arterial pressure.
Mahévas, T; Gobert, D; Gatfossé, M; Mekinian, A; Fain, O
Hepatic glycogenosis is a rare syndrome, which includes poorly controlled diabetes mellitus, hepatomegaly, delayed puberty, and growth delay. Insulin edema is sometimes associated. An 18-year-old woman presented with diffuse edema, hepatomegaly, amenorrhea, uncontrolled diabetes, and elevated transaminases and cholestasis. Hepatic ultrasonography and abdominal computed tomographic scan confirmed the hepatomegaly. The liver biopsy showed a massive glycogenosis and the diagnosis of hepatic glycogenosis was confirmed. Too large doses of insulin were responsible of diffuse edema. Diabetes equilibration and diminution of insulin intakes allow correction of this disorder. Excess of insulin can lead to excessive hepatic glycogen storage by activation of glycogenosis enzymes. Biological manifestations consist on elevated liver enzymes and hyperlactatemia. There is a link between administration of high dose of insulin and edema. Hepatic glycogenosis should be suspected when diabetes is uncontrolled and be considered as a differential diagnosis of steatosis. It may be associated and revealed by insulin edema directly related to excessive insulin intakes. Copyright © 2016 Société Nationale Française de Médecine Interne (SNFMI). Published by Elsevier SAS. All rights reserved.
Balena, R; Hensley, I E; Miller, S; Barnett, A H
Treatment algorithms for type 2 diabetes call for intensification of therapy over time as the disease progresses and glycaemic control worsens. If diet, exercise and oral antihyperglycaemic medications (OAMs) fail to maintain glycaemic control then basal insulin is added and ultimately prandial insulin may be required. However, such an intensification strategy carries risk of increased hypoglycaemia and weight gain, both of which are associated with worse long-term outcomes. An alternative strategy is to intensify therapy by the addition of a short-acting glucagon-like peptide-1 receptor agonist (GLP-1 RA) rather than prandial insulin. Short-acting GLP-1 RAs such as exenatide twice daily are particularly effective at reducing postprandial glucose while basal insulin has a greater effect on fasting glucose, providing a physiological rationale for this complementary approach. This review analyzes the latest randomized controlled clinical trials of insulin/GLP-1 RA combination therapy and examines results from ‘real-world’ use of the combinations as reported through observational and clinical practice studies. The most common finding across all types of studies was that combination therapy improved glycaemic control without weight gain or an increased risk of hypoglycaemia. Many studies reported weight loss and a reduction in insulin use when a GLP-1 RA was added to existing insulin therapy. Overall, the relative degree of benefit to glycaemic control and weight was influenced by the insulin titration employed in conjunction with the GLP-1 RA. The greatest glycaemic benefits were observed in studies with structured titration of insulin to glycaemic targets while the greatest weight benefits were observed in studies with a protocol-specified focus on insulin sparing. The adverse event profile of GLP-1 RAs in the reviewed trials was similar to that reported with GLP-1 RAs as monotherapy or in combination with OAMs with gastrointestinal events being the most commonly
Lord, J M; White, S I; Bailey, C J; Atkins, T W; Fletcher, R F; Taylor, K G
To investigate the effect of metformin on insulin receptor binding and diabetic control, eight obese type II diabetic patients were studied before treatment, after one and four weeks of taking metformin (500 mg thrice daily), and four weeks after withdrawal of the drug. After one and four weeks of treatment the number of erythrocyte insulin receptors had increased by 116% and 184% respectively. This was due almost entirely to an increase in the number of low affinity binding sites. The number of receptors was still raised four weeks after metformin had been withdrawn. Diabetic control as assessed by urinary glucose, glycosylated haemoglobin (HbA1), and glucose tolerance values was significantly improved during metformin treatment, while plasma insulin concentrations were not altered. These results indicate that metformin produces a rapid and protracted increase in low affinity insulin receptors in type II diabetes, associated with greater insulin sensitivity and improved diabetic control. PMID:6403102
Zhang, Jiquan; Wang, Jianta; Wu, Haoshu; He, Yaoyao; Zhu, Gaofeng; Cui, Xing; Tang, Lei
A series of aromatic acetic acid compounds were designed and synthesized on the basis of Non-steroidal anti-inflammatory drugs indomethacin and diclofenac. Compounds 5a, 7a, 5h, 7h and 17 could strongly promote insulin-regulated differentiation of 3T3-L1 cells in vitro. They acted as full or partial PPARgamma agonist, or improved insulin resistance through non-PPARgamma pathway.
Glendorf, Tine; Stidsen, Carsten E; Norrman, Mathias; Nishimura, Erica; Sørensen, Anders R; Kjeldsen, Thomas
.... The aim of this study was to investigate the importance of the C-terminus of the B chain in IR isoform binding in order to explore the possibility of engineering tissue-specific/liver-specific insulin analogues...
Castro G; C. Areias M.F.; Weissmann L.; Quaresma P.G.F.; Katashima C.K.; Saad M.J.A.; Prada P.O.
Insulin acts in the hypothalamus, decreasing food intake (FI) by the IR/PI3K/Akt pathway. This pathway is impaired in obese animals and endoplasmic reticulum (ER) stress and low-grade inflammation are possible mechanisms involved in this impairment. Here, we highlighted the amygdala as an important brain region for FI regulation in response to insulin. This regulation was dependent on PI3K/AKT pathway similar to the hypothalamus. Insulin was able to decrease neuropeptide Y (NPY) and increase ...
Bornfeldt, Karin E.; Tabas, Ira
Progress in preventing atherosclerotic coronary artery disease (CAD) has been stalled by the epidemic of type 2 diabetes. Further advances in this area demand a thorough understanding of how two major features of type 2 diabetes, insulin resistance and hyperglycemia, impact atherosclerosis. Insulin resistance is associated with systemic CAD risk factors, but increasing evidence suggests that defective insulin signaling in atherosclerotic lesional cells also plays an important role. The role of hyperglycemia in CAD associated with type 2 diabetes is less clear. Understanding the mechanisms whereby type 2 diabetes exacerbates CAD offers hope for new therapeutic strategies to prevent and treat atherosclerotic vascular disease. PMID:22055501
Shechter, Yoram; Maron, Ruth; Elias, Dana; Cohen, Irun R.
Mice immunized with insulin developed antibodies to both insulin and the insulin receptor. The antibodies to insulin receptor displaced labeled insulin from insulin receptors and mimicked the actions of insulin in stimulating the oxidation of glucose and its incorporation into lipids, and in inhibiting lipolysis. The antibodies to insulin receptor could be blocked by or bound to the antibodies to insulin, and therefore were identified as anti-idiotypes. Thus, immunization against a hormone may activate spontaneously an idiotype-anti-idiotype network resulting in antibodies to the hormone receptor.
Caravaggio, Fernando; Hahn, Margaret; Nakajima, Shinichiro; Gerretsen, Philip; Remington, Gary; Graff-Guerrero, Ariel
Schizophrenia is a severe and chronic neuropsychiatric disorder which affects 1% of the world population. Using the brain imaging technique positron emission tomography (PET) it has been demonstrated that persons with schizophrenia have greater dopamine transmission in the striatum compared to healthy controls. However, little progress has been made as to elucidating other biological mechanisms which may account for this hyperdopaminergic state in this disease. Studies in animals have demonstrated that insulin receptors are expressed on midbrain dopamine neurons, and that insulin from the periphery acts on these receptors to modify dopamine transmission in the striatum. This is pertinent given that several lines of evidence suggest that insulin receptor functioning may be abnormal in the brains of persons with schizophrenia. Post-mortem studies have shown that persons with schizophrenia have less than half the number of cortical insulin receptors compared to healthy persons. Moreover, these post-mortem findings are unlikely due to the effects of antipsychotic treatment; studies in cell lines and animals suggest antipsychotics enhance insulin receptor functioning. Further, hyperinsulinemia - even prior to antipsychotic use - seems to be related to less psychotic symptoms in patients with schizophrenia. Collectively, these data suggest that midbrain insulin receptor functioning may be abnormal in persons with schizophrenia, resulting in reduced insulin-mediated regulation of dopamine transmission in the striatum. Such a deficit may account for the hyperdopaminergic state observed in these patients and would help guide the development of novel treatment strategies. We hypothesize that, (i) insulin receptor expression and/or function is reduced in midbrain dopamine neurons in persons with schizophrenia, (ii) basal insulin should reduce dopaminergic transmission in the striatum via these receptors, and (iii) this modulation of dopaminergic transmission by basal insulin
Jiráček, Jiří; Žáková, Lenka
Roč. 8, Jul 27 (2017), č. článku 167. ISSN 1664-2392 R&D Projects: GA ČR GA15-19018S Institutional support: RVO:61388963 Keywords : insulin receptor * insulin binding * analog * diabetes * glucose Subject RIV: CE - Biochemistry Impact factor: 3.675, year: 2016 http:// journal .frontiersin.org/article/10.3389/fendo.2017.00167/full
Swinnen, S. G.; Dain, M.-P.; Mauricio, D.; DeVries, J. H.; Hoekstra, J. B.; Holleman, F.
We compared the combined use of basal insulin, metformin and insulin secretagogues with a combination of basal insulin and metformin in patients with type 2 diabetes starting basal insulin analogue therapy. This analysis was part of a 24-week trial, in which 964 insulin-naive patients with type 2
Ong, Ken K; Dunger, David B
Size at birth and early postnatal growth rates are important determinants of human perinatal survival; they also predict the tempo of growth, adult height and long-term risks for obesity, type 2 diabetes and cardiovascular disease. Results from the Avon Longitudinal Study of Pregnancy and Childhood (ALSPAC) show that fetal growth is influenced by both fetal genes and maternal-uterine-placental factors. Important maternal-placental factors include parity, smoking and weight gain, but also maternal genetic factors in the mother or fetal placenta, including the mitochondrial DNA 16189 variant and H19. These maternal genetic factors particularly influence smaller, growth-restrained infants, as in first pregnancies. Fetal genes include the insulin gene (INS) VNTR (variable number of tandem repeat), which we recently confirmed to be associated with birth size and cord blood IGF-II levels; these fetal gene effects are more evident in the absence of maternal-uterine growth restraint. During postnatal life, the INS VNTR III/III genotype remains associated with body size, including body mass index and waist circumference, and also lower insulin sensitivity among girls. However, as at birth, significant gene-environment interactions are seen. Rapid 'catch-up' early postnatal weight gain follows maternal-uterine restraint, and strongly predicts later childhood obesity and insulin resistance; among these children, those with INS VNTR class I alleles are more obese. Genetic factors that influence early growth may have conferred some early survival advantage in human history during times of undernutrition. With abundant nutrition and rising obesity rates, these genetic factors and their interactions with maternal and childhood environmental factors that influence childhood growth may now contribute to the early development of adult disease risk. Their recognition may help the development of targeted early interventions to prevent the progression towards adult disease.
Karbalaei, Narges; Ghasemi, Asghar; Hedayati, Mehdi; Godini, Aliashraf; Zahediasl, Saleh
Previous studies have recently shown that maternal hypothyroidism leads to impaired glucose metabolism and reduced insulin secretion in adult offspring in rats. The aim of this study was to locate the defect in the insulin secretion pathway induced by maternal hypothyroidism. Pregnant Wistar rats were divided into two groups; the control group consumed water, while the hypothyroid (FH) group received water containing 0.025% 6-propyl-2-thiouracil during gestation. An intravenous glucose tolerance test was carried out on 5-month-old male offspring. In in vitro studies, the effects of various secretagogues and inhibitors acting at different levels of the insulin secretion cascade were investigated, and insulin content, insulin secretion and glucokinase activity of the islets were compared. Although insulin content of the FH islets did not differ from that of control islets, insulin secretion from FH islets was reduced when it was challenged by glucose or arginine. Compared with control islets, activities of both hexokinase and glucokinase were also significantly decreased in the FH islets. Although, in both groups, increasing glibenclamide and nifedipine concentrations in the presence of 16.7 mmol l(-1) glucose increased and decreased insulin secretion, respectively, the percentage of changes in secretion of FH islets was significantly lower compared with control islets. The response of FH islets to high extracellular potassium concentration and diazoxide was also significantly lower than that of the control islets. These findings demonstrate that impaired insulin secretion in the FH group is probably related to alterations in different steps of the insulin secretion pathway and not in the insulin pool of β-cells.
Hollander, Priscilla A
The risk for developing type 2 diabetes (T2DM) is greater among obese individuals. Following onset of the disease, patients with T2DM become more likely to be afflicted with diabetic micro- and macrovascular complications. Decreasing body weight has been shown to lower glycosylated hemoglobin and improve other metabolic parameters in patients with T2DM. Medications used to lower blood glucose may increase body weight in patients with T2DM and this has been repeatedly shown to be the case for conventional, human insulin formulations. Insulin detemir is a neutral, soluble, long-acting insulin analog in which threonine-30 of the insulin B-chain is deleted, and the C-terminal lysine is acetylated with myristic acid, a C14 fatty acid chain. Insulin detemir binds to albumin, a property that enhances its pharmacokinetic/pharmacodynamic profile. Results from clinical trials have demonstrated that treatment with insulin detemir is associated with less weight gain than either insulin glargine or neutral protamine Hagedorn insulin. There are many potential reasons for the lower weight gain observed among patients treated with insulin detemir, including lower risk for hypoglycemia and therefore decreased defensive eating due to concern about this adverse event, along with other effects that may be related to the albumin binding of this insulin that may account for lower within-patient variability and consistent action. These might include faster transport across the blood–brain barrier, induction of satiety signaling in the brain, and preferential inhibition of hepatic glucose production versus peripheral glucose uptake. Experiments in diabetic rats have also indicated that insulin detemir increases adiponectin levels, which is associated with both weight loss and decreased eating. PMID:22291472
Castro, Gisele; C Areias, Maria Fernanda; Weissmann, Lais; Quaresma, Paula G F; Katashima, Carlos K; Saad, Mario J A; Prada, Patricia O
Insulin acts in the hypothalamus, decreasing food intake (FI) by the IR/PI3K/Akt pathway. This pathway is impaired in obese animals and endoplasmic reticulum (ER) stress and low-grade inflammation are possible mechanisms involved in this impairment. Here, we highlighted the amygdala as an important brain region for FI regulation in response to insulin. This regulation was dependent on PI3K/AKT pathway similar to the hypothalamus. Insulin was able to decrease neuropeptide Y (NPY) and increase oxytocin mRNA levels in the amygdala via PI3K, which may contribute to hypophagia. Additionally, obese rats did not reduce FI in response to insulin and AKT phosphorylation was decreased in the amygdala, suggesting insulin resistance. Insulin resistance was associated with ER stress and low-grade inflammation in this brain region. The inhibition of ER stress with PBA reverses insulin action/signaling, decreases NPY and increases oxytocin mRNA levels in the amygdala from obese rats, suggesting that ER stress is probably one of the mechanisms that induce insulin resistance in the amygdala.
Rajala, Ammaji; Dighe, Radhika; Agbaga, Martin-Paul; Anderson, Robert E; Rajala, Raju V S
.... To date there are no studies on the insulin receptor signaling in cones; however, mRNA levels of IR signaling proteins are significantly higher in cone-dominant neural retina leucine zipper (Nrl...
Raz, Itamar; Bitton, Gabriel; Klonoff, David; Nagar, Ron; Hermanns, Norbert; Haak, Thomas
Temperature changes on the surface of the skin lead to modifications of subcutaneous microcirculation. This phenomenon is employed in a standardized way by the InsuPad device to stabilize skin conditions before injections, which is associated with enhanced prandial insulin absorption. Three programmed warming cycles to 40°C within 50 minutes are resulting in faster insulin appearance in the plasma. Early standardized meal tolerance studies indicated a substantial improvement in postprandial glucose control when the same short-acting insulin analog dose was applied using InsuPad, and a dose reduction by 20% resulted in comparable glucose excursions. Similar results were obtained when patients applied the device under real-world conditions for 1 month. The InsuPad device was also tested in a prospective, controlled, parallel 3-month real-world study with 145 well-controlled but insulin-resistant patients with type 1 or type 2 diabetes. Patients were treated to target in both treatment arms (6.2 ± 0.5% in each group), with or without the device. However, patients with InsuPad needed 28% less prandial insulin, needed 12.5% less total insulin, and had 46% less confirmed hypoglycemic events (blood glucose insulin doses may result in a safer and more efficient treatment of type 1 or type 2 diabetes. PMID:25352633
Galgani, Jose E.; Moro, Cedric; Ravussin, Eric
Metabolic flexibility is the capacity for the organism to adapt fuel oxidation to fuel availability. The inability to modify fuel oxidation in response to changes in nutrient availability has been implicated in the accumulation of intramyocellular lipid and insulin resistance. The metabolic flexibility assessed by the ability to switch from fat to carbohydrate oxidation is usually impaired during a hyperinsulinemic clamp in insulin-resistant subjects; however, this “metabolic inflexibility” i...
Stamateris, Rachel E.; Sharma, Rohit B.; Kong, Yahui; Ebrahimpour, Pantea; Panday, Deepika; Ranganath, Pavana; Zou, Baobo; Levitt, Helena; Parambil, Nisha Abraham; O’Donnell, Christopher P.; García-Ocaña, Adolfo
An important goal in diabetes research is to understand the processes that trigger endogenous β-cell proliferation. Hyperglycemia induces β-cell replication, but the mechanism remains debated. A prime candidate is insulin, which acts locally through the insulin receptor. Having previously developed an in vivo mouse hyperglycemia model, we tested whether glucose induces β-cell proliferation through insulin signaling. By using mice lacking insulin signaling intermediate insulin receptor substrate 2 (IRS2), we confirmed that hyperglycemia-induced β-cell proliferation requires IRS2 both in vivo and ex vivo. Of note, insulin receptor activation was not required for glucose-induced proliferation, and insulin itself was not sufficient to drive replication. Glucose and insulin caused similar acute signaling in mouse islets, but chronic signaling differed markedly, with mammalian target of rapamycin (MTOR) and extracellular signal–related kinase (ERK) activation by glucose and AKT activation by insulin. MTOR but not ERK activation was required for glucose-induced proliferation. Cyclin D2 was necessary for glucose-induced β-cell proliferation. Cyclin D2 expression was reduced when either IRS2 or MTOR signaling was lost, and restoring cyclin D2 expression rescued the proliferation defect. Human islets shared many of these regulatory pathways. Taken together, these results support a model in which IRS2, MTOR, and cyclin D2, but not the insulin receptor, mediate glucose-induced proliferation. PMID:26740601
Full Text Available BACKGROUND: In diabetic patients, the pharmacokinetics of injected human insulin does not permit optimal control of glycemia. Fast and slow acting insulin analogues have been developed, but they may have adverse properties, such as increased mitogenic or anti-apoptotic signaling. Insulin/IGF1 hybrid receptors (IR/IGF1R, present in most tissues, have been proposed to transmit biological effects close to those of IGF1R. However, the study of hybrid receptors is difficult because of the presence of IR and IGF1R homodimers. Our objective was to perform the first study on the pharmacological properties of the five marketed insulin analogues towards IR/IGF1R hybrids. METHODOLOGY: To study the effect of insulin analogues on IR/IGF1R hybrids, we used our previously developed Bioluminescence Resonance Energy Transfer (BRET assay that permits specific analysis of the pharmacological properties of hybrid receptors. Moreover, we have developed a new, highly sensitive BRET-based assay to monitor phophatidylinositol-3 phosphate (PIP(3 production in living cells. Using this assay, we performed a detailed pharmacological analysis of PIP(3 production induced by IGF1, insulin and insulin analogues in living breast cancer-derived MCF-7 and MDA-MB231 cells. RESULTS: Among the five insulin analogues tested, only glargine stimulated IR/IGF1R hybrids with an EC50 that was significantly lower than insulin and close to that of IGF1. Glargine more efficiently stimulated PIP(3 production in MCF-7 cells but not in MDA-MB231 cells as compared to insulin. In contrast, glargine metabolites M1 and M2 showed lower potency for hybrid receptors stimulation, PIP(3 production, Akt and Erk1/2 phosphorylation and DNA synthesis in MCF-7 cells, compared to insulin. CONCLUSION: Glargine, possibly acting through IR/IGF1R hybrids, displays higher potency, whereas its metabolites M1 and M2 display lower potency than insulin for the stimulation of proliferative/anti-apoptotic pathways in
Yazıcı, Dilek; Sezer, Havva
Lipotoxicity , originally used to describe the destructive effects of excess fat accumulation on glucose metabolism, causes functional impairments in several metabolic pathways, both in adipose tissue and peripheral organs, like liver, heart, pancreas and muscle. Lipotoxicity has roles in insulin resistance and pancreatic beta cell dysfunction. Increased circulating levels of lipids and the metabolic alterations in fatty acid utilization and intracellular signaling, have been related to insulin resistance in muscle and liver. Different pathways, like novel protein kinase c pathways and the JNK-1 pathway are involved as the mechanisms of how lipotoxicity leads to insulin resistance in nonadipose tissue organs, such as liver and muscle. Mitochondrial dysfunction plays a role in the pathogenesis of insulin resistance. Endoplasmic reticulum stress, through mainly increased oxidative stress, also plays important role in the etiology of insulin resistance, especially seen in non-alcoholic fatty liver disease. Visceral adiposity and insulin resistance both increase the cardiometabolic risk and lipotoxicity seems to play a crucial role in the pathophysiology of these associations.
Iseri, K; Iyoda, M; Shikida, Y; Inokuchi, T; Morikawa, T; Hara, N; Hirano, T; Shibata, T
Type B insulin resistance syndrome is a rare disease characterized by refractory transient hyperglycaemia and severe insulin resistance associated with circulating anti-insulin receptor antibodies. A standardized treatment regimen for type B insulin resistance syndrome has yet to be established. We report the case of a 64-year-old man undergoing haemodialysis for antineutrophil cytoplasmic antibody-associated vasculitis and diabetic nephropathy, who developed rapid onset of hyperglycaemia (glycated albumin 52.1%). Type B insulin resistance syndrome was diagnosed, on the basis of positivity for anti-insulin receptor antibodies and the man's autoimmune history of antineutrophil cytoplasmic antibody-associated vasculitis and idiopathic thrombocytopenic purpura. Although severe hyperglycaemia persisted in spite of corticosteroids and high-dose insulin therapy, rituximab treatment resulted in remarkable improvement of the man's severe insulin resistance and disappearance of anti-insulin receptor antibodies without any adverse effects. According to a literature review of 11 cases in addition to the present case, rituximab appears to be a safe and effective strategy for the treatment of corticosteroid-resistant type B insulin resistance syndrome. © 2017 Diabetes UK.
Full Text Available An important disease among human metabolic disorders is type 2 diabetes mellitus. This disorder involves multiple physiological defects that result from high blood glucose content and eventually lead to the onset of insulin resistance. The combination of insulin resistance, increased glucose production, and decreased insulin secretion creates a diabetic metabolic environment that leads to a lifetime of management. Appropriate models are critical for the success of research. As such, a unique model providing insight into the mechanisms of reversible insulin resistance is mammalian hibernation. Hibernators, such as ground squirrels and bats, are excellent examples of animals exhibiting reversible insulin resistance, for which a rapid increase in body weight is required prior to entry into dormancy. Hibernator studies have shown differential regulation of specific molecular pathways involved in reversible resistance to insulin. The present review focuses on this growing area of research and the molecular mechanisms that regulate glucose homeostasis, and explores the roles of the Akt signaling pathway during hibernation. Here, we propose a link between hibernation, a well-documented response to periods of environmental stress, and reversible insulin resistance, potentially facilitated by key alterations in the Akt signaling network, PPAR-γ/PGC-1α regulation, and non-coding RNA expression. Coincidentally, many of the same pathways are frequently found to be dysregulated during insulin resistance in human type 2 diabetes. Hence, the molecular networks that may regulate reversible insulin resistance in hibernating mammals represent a novel approach by providing insight into medical treatment of insulin resistance in humans.
Wu, C-W; Biggar, K K; Storey, K B
An important disease among human metabolic disorders is type 2 diabetes mellitus. This disorder involves multiple physiological defects that result from high blood glucose content and eventually lead to the onset of insulin resistance. The combination of insulin resistance, increased glucose production, and decreased insulin secretion creates a diabetic metabolic environment that leads to a lifetime of management. Appropriate models are critical for the success of research. As such, a unique model providing insight into the mechanisms of reversible insulin resistance is mammalian hibernation. Hibernators, such as ground squirrels and bats, are excellent examples of animals exhibiting reversible insulin resistance, for which a rapid increase in body weight is required prior to entry into dormancy. Hibernator studies have shown differential regulation of specific molecular pathways involved in reversible resistance to insulin. The present review focuses on this growing area of research and the molecular mechanisms that regulate glucose homeostasis, and explores the roles of the Akt signaling pathway during hibernation. Here, we propose a link between hibernation, a well-documented response to periods of environmental stress, and reversible insulin resistance, potentially facilitated by key alterations in the Akt signaling network, PPAR-γ/PGC-1α regulation, and non-coding RNA expression. Coincidentally, many of the same pathways are frequently found to be dysregulated during insulin resistance in human type 2 diabetes. Hence, the molecular networks that may regulate reversible insulin resistance in hibernating mammals represent a novel approach by providing insight into medical treatment of insulin resistance in humans.
Wu, C-W.; Biggar, K.K.; Storey, K.B. [Carleton University, Department of Biology, Institute of Biochemistry, Ottawa, ON (Canada)
An important disease among human metabolic disorders is type 2 diabetes mellitus. This disorder involves multiple physiological defects that result from high blood glucose content and eventually lead to the onset of insulin resistance. The combination of insulin resistance, increased glucose production, and decreased insulin secretion creates a diabetic metabolic environment that leads to a lifetime of management. Appropriate models are critical for the success of research. As such, a unique model providing insight into the mechanisms of reversible insulin resistance is mammalian hibernation. Hibernators, such as ground squirrels and bats, are excellent examples of animals exhibiting reversible insulin resistance, for which a rapid increase in body weight is required prior to entry into dormancy. Hibernator studies have shown differential regulation of specific molecular pathways involved in reversible resistance to insulin. The present review focuses on this growing area of research and the molecular mechanisms that regulate glucose homeostasis, and explores the roles of the Akt signaling pathway during hibernation. Here, we propose a link between hibernation, a well-documented response to periods of environmental stress, and reversible insulin resistance, potentially facilitated by key alterations in the Akt signaling network, PPAR-γ/PGC-1α regulation, and non-coding RNA expression. Coincidentally, many of the same pathways are frequently found to be dysregulated during insulin resistance in human type 2 diabetes. Hence, the molecular networks that may regulate reversible insulin resistance in hibernating mammals represent a novel approach by providing insight into medical treatment of insulin resistance in humans.
de Galan BE
Full Text Available Bastiaan E de Galan Department of Internal Medicine, Radboud University Medical Center, Nijmegen, the Netherlands Abstract: There is ongoing interest in optimizing basal insulin treatment by developing insulins with a flat pharmacological profile, a long duration of action (typically beyond 24 hours and minimum day-to-day variation. Glargine-300 is a modified form of the long-acting insulin analog glargine in that it has been concentrated at 300 units/mL rather than the conventional 100 units/mL. Glargine-300 has a longer duration of action and a flatter pharmacological profile than original glargine-100. This property allows for more flexibility around the timing of administration, when injected once per day. Open-label studies in patients with diabetes have shown that treatment with glargine-300 achieves comparable glycemic control compared to treatment with glargine-100, albeit with consistently higher insulin requirements. These studies also showed that treatment with glargine-300 was associated with lower risks of nocturnal hypoglycemia in patients with type 2 diabetes, particularly those already on insulin, whereas data are mixed in insulin-naïve patients with type 2 diabetes or in patients with type 1 diabetes. Treatment with glargine-300 did not appear to affect the risk of overall hypoglycemia, whereas studies lacked sufficient power to investigate the effect on the risk of severe hypoglycemia. Future studies need to establish the role of glargine-300 in the treatment of diabetes alongside the other new long-acting insulin analog, insulin degludec, which was recently introduced to the market. Keywords: insulin glargine-300, type 1 diabetes, type 2 diabetes, hypoglycemia, HbA1c, patient-reported outcomes
Cordoba-Chacon, Jose; Majumdar, Neena; Pokala, Naveen K; Gahete, Manuel D; Kineman, Rhonda D
It is clear that elevations in circulating GH can lead to an increase in insulin levels. This increase in insulin may be due to GH-mediated insulin resistance and enhanced lipolysis. However, there is also in vitro and in vivo evidence that GH acts directly to increase β-cell proliferation and insulin production. Our laboratory recently developed an animal model with elevated endogenous GH levels associated with a small (25%), but significant, increase in IGF-I (HiGH mice). As expected, insulin levels were elevated in HiGH mice; however, whole body insulin sensitivity was not altered and glucose tolerance was improved. This metabolic phenotype suggests that modest elevations in circulating GH and IGF-I may enhance β-cell mass and/or function, in the absence of systemic insulin resistance, thus improving glucose homeostasis. To determine if β-cell mass and/or function is altered in HiGH mice. Male HiGH mice and their littermate controls were fed a low-fat or high-fat diet. Body composition and circulating metabolic endpoints were monitored overtime. The pancreas was recovered and processed for assessment of β-cell mass or in vitro basal and glucose-stimulated insulin secretion. HiGH mice showed elevated circulating insulin and normal glucose levels, while non-esterified FFA levels and triglycerides were reduced or normal, depending on diet and age. β-cell mass did not differ between HiGH and control mice, within diet. However, islets from HiGH mice contained and released more insulin under basal conditions, as compared to control islets, while the relative glucose-stimulated insulin release did not differ. Taken together, these results suggest moderate elevations in circulating GH and IGF-I can directly increase basal insulin secretion without impacting β-cell mass, independent of changes in whole body insulin sensitivity and hyperlipidemia. Published by Elsevier Ltd.
Abdulrasheed O Abdulrahman
Full Text Available Previous studies on the Arabian camel (Camelus dromedarius showed beneficial effects of its milk reported in diverse models of human diseases including a substantial hypoglycemic activity. However, the cellular and molecular mechanisms involved in such effects remain completely unknown. In this study, we hypothesized that camel milk may act at the level of human insulin receptor (hIR and its related intracellular signaling pathways. Therefore, we examined the effect of camel milk on the activation of hIR transiently expressed in human embryonic kidney 293 (HEK293 cells using bioluminescence resonance energy transfer (BRET technology. BRET was used to assess, in live cells and real-time, the physical interaction between hIR and insulin receptor signaling proteins (IRS1 and the growth factor receptor-bound protein 2 (Grb2. Our data showed that camel milk did not promote any increase in the BRET signal between hIR and IRS1 or Grb2 in the absence of insulin stimulation. However, it significantly potentiated the maximal insulin-promoted BRET signal between hIR and Grb2 but not IRS1. Interestingly, camel milk appears to differentially impact the downstream signaling since it significantly activated ERK1/2 and potentiated the insulin-induced ERK1/2 but not Akt activation. These observations are to some extent consistent with the BRET data since ERK1/2 and Akt activation are known to reflect the engagement of Grb2 and IRS1 pathways, respectively. The preliminary fractionation of camel milk suggests the peptide/protein nature of the active component in camel milk. Together, our study demonstrates for the first time an allosteric effect of camel milk on insulin receptor conformation and activation with differential effects on its intracellular signaling. These findings should help to shed more light on the hypoglycemic activity of camel milk with potential therapeutic applications.
Abdulrahman, Abdulrasheed O; Ismael, Mohammad A; Al-Hosaini, Khaled; Rame, Christelle; Al-Senaidy, Abdulrahman M; Dupont, Joëlle; Ayoub, Mohammed Akli
Previous studies on the Arabian camel (Camelus dromedarius) showed beneficial effects of its milk reported in diverse models of human diseases, including a substantial hypoglycemic activity. However, the cellular and molecular mechanisms involved in such effects remain completely unknown. In this study, we hypothesized that camel milk may act at the level of human insulin receptor (hIR) and its related intracellular signaling pathways. Therefore, we examined the effect of camel milk on the activation of hIR transiently expressed in human embryonic kidney 293 (HEK293) cells using bioluminescence resonance energy transfer (BRET) technology. BRET was used to assess, in live cells and real-time, the physical interaction between hIR and insulin receptor signaling proteins (IRS1) and the growth factor receptor-bound protein 2 (Grb2). Our data showed that camel milk did not promote any increase in the BRET signal between hIR and IRS1 or Grb2 in the absence of insulin stimulation. However, it significantly potentiated the maximal insulin-promoted BRET signal between hIR and Grb2 but not IRS1. Interestingly, camel milk appears to differentially impact the downstream signaling since it significantly activated ERK1/2 and potentiated the insulin-induced ERK1/2 but not Akt activation. These observations are to some extent consistent with the BRET data since ERK1/2 and Akt activation are known to reflect the engagement of Grb2 and IRS1 pathways, respectively. The preliminary fractionation of camel milk suggests the peptide/protein nature of the active component in camel milk. Together, our study demonstrates for the first time an allosteric effect of camel milk on insulin receptor conformation and activation with differential effects on its intracellular signaling. These findings should help to shed more light on the hypoglycemic activity of camel milk with potential therapeutic applications.
Abdulrahman, Abdulrasheed O.; Ismael, Mohammad A.; Al-Hosaini, Khaled; Rame, Christelle; Al-Senaidy, Abdulrahman M.; Dupont, Joëlle; Ayoub, Mohammed Akli
Previous studies on the Arabian camel (Camelus dromedarius) showed beneficial effects of its milk reported in diverse models of human diseases, including a substantial hypoglycemic activity. However, the cellular and molecular mechanisms involved in such effects remain completely unknown. In this study, we hypothesized that camel milk may act at the level of human insulin receptor (hIR) and its related intracellular signaling pathways. Therefore, we examined the effect of camel milk on the activation of hIR transiently expressed in human embryonic kidney 293 (HEK293) cells using bioluminescence resonance energy transfer (BRET) technology. BRET was used to assess, in live cells and real-time, the physical interaction between hIR and insulin receptor signaling proteins (IRS1) and the growth factor receptor-bound protein 2 (Grb2). Our data showed that camel milk did not promote any increase in the BRET signal between hIR and IRS1 or Grb2 in the absence of insulin stimulation. However, it significantly potentiated the maximal insulin-promoted BRET signal between hIR and Grb2 but not IRS1. Interestingly, camel milk appears to differentially impact the downstream signaling since it significantly activated ERK1/2 and potentiated the insulin-induced ERK1/2 but not Akt activation. These observations are to some extent consistent with the BRET data since ERK1/2 and Akt activation are known to reflect the engagement of Grb2 and IRS1 pathways, respectively. The preliminary fractionation of camel milk suggests the peptide/protein nature of the active component in camel milk. Together, our study demonstrates for the first time an allosteric effect of camel milk on insulin receptor conformation and activation with differential effects on its intracellular signaling. These findings should help to shed more light on the hypoglycemic activity of camel milk with potential therapeutic applications. PMID:26858689
Tamborlane, William V; Pfeiffer, Kathryn M; Brod, Meryl; Nikolajsen, Annie; Sandberg, Anna; Peters, Anne L; Van Name, Michelle
Despite the increased popularity of newer, fast-acting bolus insulin treatment options that allow for more flexibility in the timing of bolus insulin dosing in recent years, relatively little is known about people with diabetes who administer bolus insulin at differing times in relation to their meals. The purpose of this study was to investigate bolus insulin dose timing in relation to meals among people with type 1 (T1D) and type 2 (T2D) diabetes, as well as to better understand the characteristics and experiences of people who bolus dose at differing times. A web-based survey of adults with T1D and T2D treated with bolus insulin therapy in Germany, the UK, and USA was conducted. A total of 906 respondents completed the survey (39% T1D; 61% T2D). A majority of respondents reported bolus dosing before meals in the previous week (57.0%), followed by after meals (18.9%), with meals (12.7%), and at varying times (11.5%). Compared to respondents who dosed with or after meals, those who dosed before meals were significantly less likely to experience hypoglycemia (before, 55.7%; with, 72.8%; after, 68.7%; p insulin with or after meals. Key limitations of all self-report surveys include potential bias in responses and generalizability of findings. However, the study was designed to help mitigate these limitations. The findings have implications for clinicians and suggest opportunities for improving diabetes education and care.
Lamontagne, Julien; Jalbert-Arsenault, Elise; Pepin, Emilie; Peyot, Marie-Line; Ruderman, Neil B; Nolan, Christopher J; Joly, Erik; Madiraju, S R Murthy; Poitout, Vincent; Prentki, Marc
Our objective was to determine if the insulin-sensitizing drug pioglitazone acutely reduces insulin secretion and causes metabolic deceleration in vivo independently of change in insulin sensitivity...
Søeborg, Tue; Rasmussen, Christian Hove; Mosekilde, Erik
Absorption of subcutaneously administered insulin is associated with considerable variability. Some of this variability was quantitatively explained for both soluble insulin and insulin suspensions in a recent contribution to this journal (Søeborg et al., 2009). In the present article......, the absorption kinetics for mixtures of insulins is described. This requires that the bioavailability of the different insulins is considered. A short review of insulin bioavailability and a description of the subcutaneous depot thus precede the presentation of possible mechanisms associated with subcutaneous...... insulin degradation. Soluble insulins are assumed to be degraded enzymatically in the subcutaneous tissue. Suspended insulin crystals form condensed heaps that are assumed to be degraded from their surface by invading macrophages. It is demonstrated how the shape of the heaps affects the absorption...
Full Text Available Although the brain has been considered an insulin-insensitive organ, recent reports on the location of insulin and its receptors in the brain have introduced new ways of considering this hormone responsible for several functions. The origin of insulin in the brain has been explained from peripheral or central sources, or both. Regardless of whether insulin is of peripheral origin or produced in the brain, this hormone may act through its own receptors present in the brain. The molecular events through which insulin functions in the brain are the same as those operating in the periphery. However, certain insulin actions are different in the CNS, such as hormone-induced glucose uptake due to a low insulin-sensitive GLUT-4 activity, and because of the predominant presence of GLUT-1 and GLUT-3. In addition, insulin in the brain contributes to the control of nutrient homeostasis, reproduction, cognition and memory, as well as to neurotrophic, neuromodulatory, and neuroprotective effects. Alterations of these functional activities may contribute to the manifestation of several clinical entities, such as central insulin resistance, type 2 diabetes (T2DM and Alzheimer’s disease (AD. A close association between T2DM and AD has been reported, to the extent that AD is twice more frequent in diabetic patients, and some authors have proposed the name type 3 diabetes for this association. There are links between AD and type 2 diabetes mellitus (T2DM through mitochondrial alterations and oxidative stress, altered energy and glucose metabolism, cholesterol modifications, dysfunctional protein OGlcNAcylation, formation of amyloid plaques, altered Aβ metabolism, and tau hyperphosphorylation. Advances in the knowledge of preclinical AD and T2DM may be a major stimulus for the development of treatment for preventing the pathogenic events of
Head, W Steven; Orseth, Meredith L; Nunemaker, Craig S; Satin, Leslie S; Piston, David W; Benninger, Richard K P
Insulin is secreted from the islets of Langerhans in coordinated pulses. These pulses are thought to lead to plasma insulin oscillations, which are putatively more effective in lowering blood glucose than continuous levels of insulin. Gap-junction coupling of β-cells by connexin-36 coordinates intracellular free calcium oscillations and pulsatile insulin release in isolated islets, however a role in vivo has not been shown. We test whether loss of gap-junction coupling disrupts plasma insulin oscillations and whether this impacts glucose tolerance. We characterized the connexin-36 knockout (Cx36(-/-)) mouse phenotype and performed hyperglycemic clamps with rapid sampling of insulin in Cx36(-/-) and control mice. Our results show that Cx36(-/-) mice are glucose intolerant, despite normal plasma insulin levels and insulin sensitivity. However, Cx36(-/-) mice exhibit reduced insulin pulse amplitudes and a reduction in first-phase insulin secretion. These changes are similarly found in isolated Cx36(-/-) islets. We conclude that Cx36 gap junctions regulate the in vivo dynamics of insulin secretion, which in turn is important for glucose homeostasis. Coordinated pulsatility of individual islets enhances the first-phase elevation and second-phase pulses of insulin. Because these dynamics are disrupted in the early stages of type 2 diabetes, dysregulation of gap-junction coupling could be an important factor in the development of this disease.
Rami A. Ballout
Full Text Available A 56-year-old middle-eastern male with a long-standing history of poorly controlled type 2 diabetes mellitus presented to us complaining of severely painful bilateral upper and lower extremity cramps occurring shortly after his rapid-acting insulin analog injection(s. The cramps had started 6 months ago and have been occurring intermittently in non-predictable episodes since then. He had otherwise never experienced any insulin-related adverse reaction(s before. His cramps are very painful and debilitating, interfering with his daily activities and placing him in a state of constant fear/anxiety of re-experiencing them. This caused him to become non-adherent with his prescribed treatment and poorly compliant with his follow-up regimens. Thorough examination showed a diffuse loss of sensation over the lower limbs. This was subsequently confirmed with a combined electromyography–nerve conduction study which indicated extensive diabetic axonal polyneuropathy. By contrast, lower extremity segmental arterial pressures were negative for peripheral vasculo-occlusive disease, ruling out vascular insufficiency as a possible etiology of the cramps. We then measured the levels of serum electrolytes right-before and 30 min right-after injecting the patient with his insulin. Potassium dropped by about 16% from its initial level, compared to a drop of only around 4% for calcium and none (0% for magnesium. Thus, we speculated this insulin-induced sharp drop in serum potassium levels as potentiating the patient’s already existing advanced diabetic neuropathy, thereby leading to muscle cramping. However, attempting potassium supplementation for a brief period of time led to a rapid resolution of cramps when they occurred and an overall reduction in their frequency of recurrence. This tilted our diagnosis toward the insulin-induced acute drop in serum potassium levels as the most likely etiology underlying the patient’s cramps. Such an observation has
Full Text Available Preclinical, early phase clinical trials and epidemiological evidence support the potential role of insulin-sensitizers in cancer prevention and treatment. Insulin-sensitizers improve the metabolic and hormonal profile in PCOS patients and may also act as anticancer agents, especially in cancers associated with hyperinsulinemia and oestrogen dependent cancers. Several lines of evidence support the protection against cancer exerted by dietary inositol, in particular inositol hexaphosphate. Metformin, thiazolidinediones, and myoinositol postreceptor signaling may exhibit direct inhibitory effects on cancer cell growth. AMPK, the main molecular target of metformin, is emerging as a target for cancer prevention and treatment. PCOS may be correlated to an increased risk for developing ovarian and endometrial cancer (up to threefold. Several studies have demonstrated an increase in mortality rate from ovarian cancer among overweight/obese PCOS women compared with normal weight women. Long-term use of metformin has been associated with lower rates of ovarian cancer. Considering the evidence supporting a higher risk of gynaecological cancer in PCOS women, we discuss the potential use of insulin-sensitizers as a potential tool for chemoprevention, hypothesizing a possible rationale through which insulin-sensitizers may inhibit tumourigenesis.
Lauretta, Rosa; Lanzolla, Giulia; Vici, Patrizia; Mariani, Luciano; Moretti, Costanzo
Preclinical, early phase clinical trials and epidemiological evidence support the potential role of insulin-sensitizers in cancer prevention and treatment. Insulin-sensitizers improve the metabolic and hormonal profile in PCOS patients and may also act as anticancer agents, especially in cancers associated with hyperinsulinemia and oestrogen dependent cancers. Several lines of evidence support the protection against cancer exerted by dietary inositol, in particular inositol hexaphosphate. Metformin, thiazolidinediones, and myoinositol postreceptor signaling may exhibit direct inhibitory effects on cancer cell growth. AMPK, the main molecular target of metformin, is emerging as a target for cancer prevention and treatment. PCOS may be correlated to an increased risk for developing ovarian and endometrial cancer (up to threefold). Several studies have demonstrated an increase in mortality rate from ovarian cancer among overweight/obese PCOS women compared with normal weight women. Long-term use of metformin has been associated with lower rates of ovarian cancer. Considering the evidence supporting a higher risk of gynaecological cancer in PCOS women, we discuss the potential use of insulin-sensitizers as a potential tool for chemoprevention, hypothesizing a possible rationale through which insulin-sensitizers may inhibit tumourigenesis. PMID:27725832
Hamishehkar, Hamed; Emami, Jaber; Najafabadi, Abdolhossien Rouholamini; Gilani, Kambiz; Minaiyan, Mohsen; Hassanzadeh, Kambiz; Mahdavi, Hamid; Koohsoltani, Maryam; Nokhodchi, Ali
The pulmonary route is an alternative route of administration for the systemic delivery of peptide and proteins with short-half lives. A long-acting formulation of insulin was prepared by encapsulation of protein into respirable, biodegradable microcapsules prepared by an oil in oil emulsification/solvent evaporation method. Insulin-loaded PLGA microcapsules prepared as a dry powder inhaler formulation were administered via the pulmonary route to diabetic rats and serum insulin and glucose concentrations were monitored. Control treatments consisted of respirable spray-dried insulin (RSDI) powder administered by intratracheal insufflation, insulin-loaded PLGA microcapsules and NPH (long-acting) insulin administered by subcutaneous (SC) administration. Pharmacokinetic analysis demonstrated that insulin administered in PLGA microcapsules illustrated a sustained release profile which resulted in a longer mean residence time, 4 and 5 fold longer than those after pulmonary administration of RSDI and SC injection of NPH insulin, respectively. Accordingly, the hypoglycemic profile followed a stable and sustained pattern which remained constant between 10 and 48 h. Results of the in vitro experiments were in good agreement with those of in vivo studies. Bronchoalveolar lavage fluid analysis indicated that microcapsules administration did not increase the activities of lactate dehydrogenase and total protein. However, histological examination of the lung tissue indicated a minor but detectable effect on the normal physiology of the rat lung. These findings suggest that the encapsulation of peptides and proteins into PLGA microcapsules technique could be a promising controlled delivery system for pulmonary administration. Copyright (c) 2010 John Wiley & Sons, Ltd.
Gordon, Jason; Evans, Marc; McEwan, Phil; Bain, Steve; Vora, Jiten
It is unclear as to whether human or long-acting analog insulins represent the most efficient use of health and non-healthcare resources in the management of type 2 diabetes mellitus (T2DM). The aim of this study was to evaluate the value for money relationship associated with the use of these insulins in the UK setting. A literature search was performed for studies reporting expenditure associated with the use of human and analog insulins. Data from this review informed a budget impact assessment model. Costs were converted to a common currency and results are reported in 2011 British pounds sterling (GBP) values. Annual diabetes-related medication expenditure and patients total expenditure associated with the management of T2DM were estimated to be £397 million and £3,901 million, respectively. Substitution of human insulin for analog insulins was associated with a drug acquisition cost saving of between £5 million and £23 million each year. Overall, though, total expenditure increased significantly with increased use of human insulin by £34 million to £136 million each year depending on the degree of substitution. On the face of it, analog insulins are more expensive, prompting questions about potential cost savings to health services in the UK from direct substitution to the less expensive human preparation. The current analysis illustrates that the increased use of human insulin and decreased use of analog insulin would, however, increase the overall net societal cost of managing insulin-treated patients with T2DM. Governments and decision makers should consider that total healthcare expenditure would not necessarily fall when decisions are based solely on the use of cheaper products.
Chen, Hui; Hong, Feng; Chen, Ye; Li, Ji; Yao, Yuan-Sheng; Zhang, Yue; Zheng, Li-Fei; Zhu, Jin-Xia
Mosapride, a gastrointestinal prokinetic drug, is an agonist of 5-hydroxytryptamine (5-HT) receptor 4 that also reduces blood glucose. Whether 5-HT4 receptor is distributed in pancreatic islets and whether mosapride can directly stimulate insulin secretion is unclear. In the present study, the protein expression and cellular location of 5-HT4 receptor in pancreas was detected through western blotting and immunofluorescence. The acute effects of 5-HT4 receptor agonists, mosapride and prucalopride, on insulin secretion were investigated in vivo and in vitro in normal and alloxan-induced diabetes rats. The results indicated that 5-HT4 receptor immunoreactivity was co-existed in the islets insulin-immunoreactive cells of rat, mouse, pig and human. However the immunoreactive cells of insulin and 5-HT4 receptor and the protein expression of 5-HT4 receptor were significantly decreased in the pancreas of alloxan-induced diabetes rats. In normal rats, mosapride and prucalopride decreased blood glucose and increased insulin secretion during glucose tolerance test, in association with an increase in glucose-stimulated insulin secretion, which was abolished by the 5-HT4 receptor antagonist GR113808. In diabetes rats, mosapride and prucalopride failed to improve blood glucose and insulin levels in the group of 180mg/kg alloxan, but increased glucose-stimulated insulin secretion in the group of 120mg/kg alloxan in vitro. We conclude that 5-HT4 receptor is distributed in the islet β cell. Activation of 5-HT4 receptor is able to stimulate insulin secretion directly, thereby reduce blood glucose. The study provides important experimental evidences for the 5-HT4 receptor regulating insulin secretion and acting as a potential drug target in diabetes treatment. Copyright © 2016 Elsevier B.V. All rights reserved.
But, Anna; De Bruin, Marie L.; Bazelier, Marloes T.
AIMS/HYPOTHESIS: The aim of this work was to investigate the relationship between use of certain insulins and risk for cancer, when addressing the limitations and biases involved in previous studies. METHODS: National Health Registries from Denmark (1996-2010), Finland (1996-2011), Norway (2005......-2010) and Sweden (2007-2012) and the UK Clinical Practice Research Datalink database (1987-2013) were used to conduct a cohort study on new insulin users (N = 327,112). By using a common data model and semi-aggregate approach, we pooled individual-level records from five cohorts and applied Poisson regression...... models. For each of ten cancer sites studied, we estimated the rate ratios (RRs) by duration (≤0.5, 0.5-1, 1-2, 2-3, 3-4, 4-5, 5-6 and >6 years) of cumulative exposure to insulin glargine or insulin detemir relative to that of human insulin. RESULTS: A total of 21,390 cancer cases occurred during a mean...
Full Text Available Ip Tim Lau,1 Ka Fai Lee,2 Wing Yee So,3 Kathryn Tan,4 Vincent Tok Fai Yeung5 1Department of Medicine, Tseung Kwan O Hospital, 2Department of Medicine and Geriatrics, Kwong Wah Hospital, 3Department of Medicine and Therapeutics, Chinese University of Hong Kong, Prince of Wales Hospital, 4Department of Medicine, Queen Mary Hospital, University of Hong Kong, 5Department of Medicine and Geriatrics, Our Lady of Maryknoll Hospital, Hong Kong, China Objective: To review published clinical studies on the efficacy and safety of new insulin glargine 300 units/mL (Gla-300, a new long-acting insulin analog, for the treatment of type 1 and type 2 diabetes mellitus (T1DM, T2DMMaterials and methods: Data sources comprised primary research articles on Gla-300, including pharmacodynamic, pharmacokinetic, and clinical studies.Results: In pharmacodynamic and pharmacokinetic studies, Gla-300 showed a flatter time–action profile and longer duration of action than Gla-100. Noninferiority of Gla-300 versus Gla-100 for lowering of glycated hemoglobin was demonstrated in Phase III clinical studies covering a range of T1DM and T2DM patient populations. Over 6–12 months of follow-up, Gla-300 consistently showed comparable glycemic efficacy with less hypoglycemia vs Gla-100, even during the first 8 weeks of treatment. Although titrated insulin doses were 11%–17% higher with Gla-300 vs Gla-100, changes in body weight were similar or favored Gla-300.Conclusion: Clinical studies provide evidence that the pharmacodynamic and pharmacokinetic properties of Gla-300 may translate into clinical benefits in both T1DM and T2DM. Gla-300 may provide a new option for people initiating basal insulin, those requiring higher basal insulin doses, those with T1DM, and those who may be at increased risk for hypoglycemia, such as people with chronic kidney disease, the elderly, and those with cardiovascular comorbidities. Keywords: diabetes mellitus, long-acting insulin, insulin glargine
Full Text Available Diabetes mellitus (DM is an important health problem that should be treated efficiently because of its high prevalence and high morbidity and mortality due to its complications. In patients with DM, the application of a treatment which provides physiologic insulin secretion as such in healthy individuals is directly related with the prevention of diabetes complications. Insulin analogs, which were developed in recent years and shown to have pharmacokinetic and pharmacodynamic superiority to human insulin, have made it possible to obtain natural insulin pattern in the body. In addition to development of insulin analogs, introduction of insulin application method of “continuous subcutaneous insulin infusion” (insulin pump has led a new era in the treatment of DM. In this review, treatment of type 1 and 2 DM patients with insulin analogs, particularly insulin aspart, applied with insulin pump was discussed in the light of the current literature.
Full Text Available BACKGROUND: The insulin receptor (IR exists in two isoforms, A and B, and the isoform expression pattern is tissue-specific. The C-terminus of the insulin B chain is important for receptor binding and has been shown to contact the IR just adjacent to the region where the A and B isoforms differ. The aim of this study was to investigate the importance of the C-terminus of the B chain in IR isoform binding in order to explore the possibility of engineering tissue-specific/liver-specific insulin analogues. METHODOLOGY/PRINCIPAL FINDINGS: Insulin analogue libraries were constructed by total amino acid scanning mutagenesis. The relative binding affinities for the A and B isoform of the IR were determined by competition assays using scintillation proximity assay technology. Structural information was obtained by X-ray crystallography. Introduction of B25A or B25N mutations resulted in analogues with a 2-fold preference for the B compared to the A isoform, whereas the opposite was observed with a B25Y substitution. An acidic amino acid residue at position B27 caused an additional 2-fold selective increase in affinity for the receptor B isoform for analogues bearing a B25N mutation. Furthermore, the combination of B25H with either B27D or B27E also resulted in B isoform-preferential analogues (2-fold preference even though the corresponding single mutation analogues displayed no differences in relative isoform binding affinity. CONCLUSIONS/SIGNIFICANCE: We have discovered a new class of IR isoform-selective insulin analogues with 2-4-fold differences in relative binding affinities for either the A or the B isoform of the IR compared to human insulin. Our results demonstrate that a mutation at position B25 alone or in combination with a mutation at position B27 in the insulin molecule confers IR isoform selectivity. Isoform-preferential analogues may provide new opportunities for developing insulin analogues with improved clinical benefits.
Glendorf, Tine; Stidsen, Carsten E.; Norrman, Mathias; Nishimura, Erica; Sørensen, Anders R.; Kjeldsen, Thomas
Background The insulin receptor (IR) exists in two isoforms, A and B, and the isoform expression pattern is tissue-specific. The C-terminus of the insulin B chain is important for receptor binding and has been shown to contact the IR just adjacent to the region where the A and B isoforms differ. The aim of this study was to investigate the importance of the C-terminus of the B chain in IR isoform binding in order to explore the possibility of engineering tissue-specific/liver-specific insulin analogues. Methodology/Principal Findings Insulin analogue libraries were constructed by total amino acid scanning mutagenesis. The relative binding affinities for the A and B isoform of the IR were determined by competition assays using scintillation proximity assay technology. Structural information was obtained by X-ray crystallography. Introduction of B25A or B25N mutations resulted in analogues with a 2-fold preference for the B compared to the A isoform, whereas the opposite was observed with a B25Y substitution. An acidic amino acid residue at position B27 caused an additional 2-fold selective increase in affinity for the receptor B isoform for analogues bearing a B25N mutation. Furthermore, the combination of B25H with either B27D or B27E also resulted in B isoform-preferential analogues (2-fold preference) even though the corresponding single mutation analogues displayed no differences in relative isoform binding affinity. Conclusions/Significance We have discovered a new class of IR isoform-selective insulin analogues with 2–4-fold differences in relative binding affinities for either the A or the B isoform of the IR compared to human insulin. Our results demonstrate that a mutation at position B25 alone or in combination with a mutation at position B27 in the insulin molecule confers IR isoform selectivity. Isoform-preferential analogues may provide new opportunities for developing insulin analogues with improved clinical benefits. PMID:21625452
Luana Mota Martins
Full Text Available White adipose tissue (WAT is considered an endocrine organ. When present in excess, WAT can influence metabolism via biologically active molecules. Following unregulated production of such molecules, adipose tissue dysfunction results, contributing to complications associated with obesity. Previous studies have implicated pro- and anti-inflammatory substances in the regulation of inflammatory response and in the development of insulin resistance. In obese individuals, pro-inflammatory molecules produced by adipose tissue contribute to the development of insulin resistance and increased risk of cardiovascular disease. On the other hand, the molecules with anti-inflammatory action, that have been associated with the improvement of insulin sensitivity, have your decreased production. Imbalance of these substances contributes significantly to metabolic disorders found in obese individuals. The current review aims to provide updated information regarding the activity of biomolecules produced by WAT.
Pearson-Leary, Jiah; McNay, Ewan C.
Increasing evidence suggests that abnormal brain accumulation of amyloid-β1–42 (Aβ1–42) oligomers plays a causal role in Alzheimer’s disease (AD), and in particular may cause the cognitive deficits that are the hallmark of AD. In vitro, Aβ1–42 oligomers impair insulin signaling and suppress neural functioning. We previously showed that endogenous insulin signaling is an obligatory component of normal hippocampal function, and that disrupting this signaling led to a rapid impairment of spatial working memory, while delivery of exogenous insulin to the hippocampus enhanced both memory and metabolism; diet-induced insulin resistance both impaired spatial memory and prevented insulin from increasing metabolism or cognitive function. Hence, we tested the hypothesis that Aβ1–42 oligomers could acutely impair hippocampal metabolic and cognitive processes in vivo in the rat. Our findings support this hypothesis: Aβ1–42 oligomers impaired spontaneous alternation behavior while preventing the task-associated dip in hippocampal ECF glucose observed in control animals. In addition, Aβ1–42 oligomers decreased plasma membrane translocation of the insulin-sensitive glucose transporter 4 (GluT4), and impaired insulin signaling as measured by phosphorylation of Akt. These data show in vivo that Aβ1–42 oligomers can rapidly impair hippocampal cognitive and metabolic processes, and provide support for the hypothesis that elevated Aβ1–42 leads to cognitive impairment via interference with hippocampal insulin signaling. PMID:22430529
Pearson-Leary, Jiah; McNay, Ewan C
Increasing evidence suggests that abnormal brain accumulation of amyloid-β(1-42) (Aβ(1-42)) oligomers plays a causal role in Alzheimer's disease (AD), and in particular may cause the cognitive deficits that are the hallmark of AD. In vitro, Aβ(1-42) oligomers impair insulin signaling and suppress neural functioning. We previously showed that endogenous insulin signaling is an obligatory component of normal hippocampal function, and that disrupting this signaling led to a rapid impairment of spatial working memory, while delivery of exogenous insulin to the hippocampus enhanced both memory and metabolism; diet-induced insulin resistance both impaired spatial memory and prevented insulin from increasing metabolism or cognitive function. Hence, we tested the hypothesis that Aβ(1-42) oligomers could acutely impair hippocampal metabolic and cognitive processes in vivo in the rat. Our findings support this hypothesis: Aβ(1-42) oligomers impaired spontaneous alternation behavior while preventing the task-associated dip in hippocampal ECF glucose observed in control animals. In addition, Aβ(1-42) oligomers decreased plasma membrane translocation of the insulin-sensitive glucose transporter 4 (GluT4), and impaired insulin signaling as measured by phosphorylation of Akt. These data show in vivo that Aβ(1-42) oligomers can rapidly impair hippocampal cognitive and metabolic processes, and provide support for the hypothesis that elevated Aβ(1-42) leads to cognitive impairment via interference with hippocampal insulin signaling.
Rodbard, H W; Cariou, B; Zinman, B
The aim of this study was to compare long-term safety and efficacy of the basal insulin analogue degludec with glargine in insulin-naive subjects with Type 2 diabetes.......The aim of this study was to compare long-term safety and efficacy of the basal insulin analogue degludec with glargine in insulin-naive subjects with Type 2 diabetes....
Park, Yong-Moon; Zhang, Jiajia; Steck, Susan E; Fung, Teresa T; Hazlett, Linda J; Han, Kyungdo; Ko, Seung-Hyun; Merchant, Anwar T
Background: The inverse association between Mediterranean diet (Med-diet) consumption and insulin resistance or inflammatory markers is well known. However, the extent to which obesity may act directly on or mediate this association is unclear.Objective: We aimed to investigate whether the associations between Med-diet consumption and markers of insulin resistance and inflammation are mediated by body mass index (BMI) or waist circumference (WC) in a representative US population.Methods: We used cross-sectional data from 4700 adults aged 20-90 y without any previous diagnosis of cancer, cardiovascular disease, diabetes, or hypertension based on the NHANES III, 1988-1994. A Med-diet score (MDS) was created to assess adherence to the Med-diet. Linear regression models were fitted in conventional and causal mediation analyses comparing extreme MDS tertiles.Results: Compared with the lowest MDS tertile, the highest tertile of MDS was associated with a 0.77 lower BMI (in kg/m(2); P = 0.004) and a 2.7 cm lower WC (P insulin resistance and glucose intolerance markers (log insulin, log homoeostasis model assessment of insulin resistance, fasting glucose, and glycated hemoglobin) and inflammatory markers (white blood cell count and fibrinogen), whereas BMI mediated the association between MDS and insulin resistance and glucose intolerance markers only (all P obesity may play an important role in the pathway through which Med-diet consumption reduces insulin resistance and inflammation. © 2017 American Society for Nutrition.
Di Meo, Sergio; Iossa, Susanna; Venditti, Paola
Obesity-linked insulin resistance is mainly due to fatty acid overload in non-adipose tissues, particularly skeletal muscle and liver, where it results in high production of reactive oxygen species and mitochondrial dysfunction. Accumulating evidence indicates that resistance and endurance training alone and in combination can counteract the harmful effects of obesity increasing insulin sensitivity, thus preventing diabetes. This review focuses the mechanisms underlying the exercise role in opposing skeletal muscle insulin resistance-linked metabolic dysfunction. It is apparent that exercise acts through two mechanisms: (1) it stimulates glucose transport by activating an insulin-independent pathway and (2) it protects against mitochondrial dysfunction-induced insulin resistance by increasing muscle antioxidant defenses and mitochondrial biogenesis. However, antioxidant supplementation combined with endurance training increases glucose transport in insulin-resistant skeletal muscle in an additive fashion only when antioxidants that are able to increase the expression of antioxidant enzymes and/or the activity of components of the insulin signaling pathway are used. © 2017 Society for Endocrinology.
Rodbard, Helena W
The ADA/EASD and AACE guidelines emphasize the importance of individualizing treatment to best meet each patient's situation. Metformin remains the preferred choice as initial therapy for most patients. The 2009 AACE algorithm elevated the role of incretin-based therapies (GLP-1R agonists and DPP-4 inhibitors) relative to previous algorithms and this has been endorsed by subsequent algorithms and guidelines. The incretin-based therapies and insulin therapy should be considered with very high priority. Either incretin-based therapy or insulin therapy can be used as monotherapy or in combination with other agents. The GLP-1R agonists are especially useful when attempting to reduce the risk of hypoglycemia and when assisting the patient to achieve weight loss. Insulin therapy is especially useful when the HbA1c level is >9.0% or when symptoms of glucotoxicity are present. Insulin is the recommended treatment when other agents fail to achieve the desired target levels for HbA1c, FPG, and PPG. The combination of a GLP-1R agonist with basal insulin can provide better glycemic control than either agent alone, with less weight gain and glycemic outcomes for combined therapy with a long-acting basal insulin analog and a glucagon-like peptide-1 receptor agonist a markedly lower incidence of hypoglycemia than with use of basal insulin alone.
Agrawal, Siddarth; Łuc, Mateusz; Ziółkowski, Piotr; Agrawal, Anil Kumar; Pielka, Ewa; Walaszek, Kinga; Zduniak, Krzysztof; Woźniak, Marta
The study was designed to evaluate the potential use of insulin for cancer-specific treatment. Insulin-induced sensitivity of MCF-7 breast cancer cells to chemotherapeutic agents 5-fluorouracil and cyclophosphamide was evaluated. To investigate and establish the possible mechanisms of this phenomenon, we assessed cell proliferation, induction of apoptosis, activation of apoptotic and autophagic pathways, expression of glucose transporters 1 and 3, formation of reactive oxygen species, and wound-healing assay. Additionally, we reviewed the literature regarding theuse of insulin in cancer-specific treatment. We found that insulin increases the cytotoxic effect of 5-fluorouracil and cyclophosphamide in vitro up to two-fold. The effect was linked to enhancement of apoptosis, activation of apoptotic and autophagic pathways, and overexpression of glucose transporters 1 and 3 as well as inhibition of cell proliferation and motility. We propose a model for insulin-induced sensitization process. Insulin acts as a sensitizer of cancer cells to cytotoxic therapy through various mechanisms opening a possibility for metronomic insulin-based treatments.
Yang, Xuefeng; Mei, Shuang; Gu, Haihua; Guo, Huailan; Zha, Longying; Cai, Junwei; Li, Xuefeng; Liu, Zhenqi; Cao, Wenhong
We have previously shown that insulin plays an important role in the nutrient-induced insulin resistance. In this study, we tested the hypothesis that chronic exposure to excess long-acting insulin (glargine) can cause typical type 2 diabetes mellitus (T2DM) in normal mice fed on a chow diet. C57BL/6 mice were treated with glargine once a day for 8 weeks, followed by evaluations of food intake, body weight, blood levels of glucose, insulin, lipids, and cytokines, insulin signaling, histology of pancreas, ectopic fat accumulation, oxidative stress level, and cholesterol content in mitochondria in tissues. Cholesterol content in mitochondria and its association with oxidative stress in cultured hepatocytes and β-cells were also examined. Results show that chronic exposure to glargine caused insulin resistance, hyperinsulinemia, and relative insulin deficiency (T2DM). Treatment with excess glargine led to loss of pancreatic islets, ectopic fat accumulation in liver, oxidative stress in liver and pancreas, and increased cholesterol content in mitochondria of liver and pancreas. Prolonged exposure of cultured primary hepatocytes and HIT-TI5 β-cells to insulin induced oxidative stress in a cholesterol synthesis-dependent manner. Together, our results show that chronic exposure to excess insulin can induce typical T2DM in normal mice fed on a chow diet. © 2014 The authors.
Fort, Patrice E.; Losiewicz, Mandy K.; Reiter, Chad E. N.; Singh, Ravi S. J.; Nakamura, Makoto; Abcouwer, Steven F.; Barber, Alistair J.; Gardner, Thomas W.
Diabetes pathology derives from the combination of hyperglycemia and hypoinsulinemia or insulin resistance leading to diabetic complications including diabetic neuropathy, nephropathy and retinopathy. Diabetic retinopathy is characterized by numerous retinal defects affecting the vasculature and the neuro-retina, but the relative contributions of the loss of retinal insulin signaling and hyperglycemia have never been directly compared. In this study we tested the hypothesis that increased retinal insulin signaling and glycemic normalization would exert differential effects on retinal cell survival and retinal physiology during diabetes. We have demonstrated in this study that both subconjunctival insulin administration and systemic glycemic reduction using the sodium-glucose linked transporter inhibitor phloridzin affected the regulation of retinal cell survival in diabetic rats. Both treatments partially restored the retinal insulin signaling without increasing plasma insulin levels. Retinal transcriptomic and histological analysis also clearly demonstrated that local administration of insulin and systemic glycemia normalization use different pathways to counteract the effects of diabetes on the retina. While local insulin primarily affected inflammation-associated pathways, systemic glycemic control affected pathways involved in the regulation of cell signaling and metabolism. These results suggest that hyperglycemia induces resistance to growth factor action in the retina and clearly demonstrate that both restoration of glycemic control and retinal insulin signaling can act through different pathways to both normalize diabetes-induced retinal abnormality and prevent vision loss. PMID:22046295
Kaplan, Warren A; Beall, Reed F
Lack of access to insulin and poor health outcomes are issues for both low and high income countries. This has been accompanied by a shift from relatively inexpensive human insulin to its more expensive analogs, marketed by three to four main global players. Nonetheless, patent-based market exclusivities are beginning to expire there for the first generation insulin analogs. This paper adds a global dimension to information on the U.S. patent landscape for insulin by reviewing the patent status of insulins with emphasis on the situation outside the US and Europe. Using the term "insulin", we searched for patents listed on the United States Food and Drug Administration's (USFDA) Orange Book and the Canadian Online Drug Product Database Online Query and its Patent Register. With this information, we expanded the search globally using the World Intellectual Property Organization (WIPO) PatentScope database, the European Patent Office's INPADOC database and various country-specific Patent Offices. Patent protected insulins marketed in the U.S. and other countries are facing an imminent patent-expiration "cliff' yet the three companies that dominate the global insulin market are continuing to file for patents in and outside the U.S, but very rarely in Africa. Only a few local producers in the so-called "pharmerging" markets (e.g., Brazil, India, China) are filing for global patent protection on their own insulins. There is moderate, but statistically significant association between patent filings and diabetes disease burden. The global market dominance by a few companies of analog over human insulin will likely continue even though patents on the current portfolio of insulin analogs will expire very soon. Multinationals are continuing to file for more insulin patents in the bigger markets with large disease burdens and a rapidly emerging middle class. Off-patent human insulins can effectively manage diabetes. A practical way forward would be find (potential) generic
Jensen, Vivi Flou Hjorth; Mølck, Anne-Marie; Heydenreich, Annette
New insulin analogues with a longer duration of action and a flatter pharmacodynamic profile are developed to improve convenience and safety for diabetic patients. During the nonclinical development of such analogues, safety studies must be conducted in nondiabetic rats, which consequently...... are rendered chronically hypoglycemic. A rat comparator model using human insulin would be valuable, as it would enable differentiation between effects related to either persistent insulin-induced hypoglycemia (IIH) or a new analogue per se. Such a model could alleviate the need for an in...... nerve and skeletal myofiber degeneration within the same animals. This suggests that the model can serve as a nonclinical comparator model during development of long-acting insulin analogues....
Gregersen, S; Thomsen, J L; Brock, B
Endothelin-1 (ET-1), a potent endothelium-derived vasoconstrictor peptide, is secreted in response to insulin. Elevated circulating ET-1 levels have been found in patients with diabetes mellitus and vascular dysfunction. The question arises whether ET-1 acts as a direct modulator of insulin...... secretion. To test this, we studied the effects of ET-1 on isolated mouse islets of Langerhans. ET-1 (1 nmol/l-1 mumol/l) dose-dependently stimulated insulin secretion from islets incubated in the presence of 16.7 mmol/l glucose (p ... was found at 3.3 mmol/l glucose. Furthermore, ET-1 induced a large, transient increase in glucose-stimulated insulin secretion during islet perifusion in the presence (p
Morris, Siti Nur Sarah; Coogan, Claire; Chamseddin, Khalil; Fernandez-Kim, Sun Ok; Kolli, Santharam; Keller, Jeffrey N; Bauer, Johannes H
The fruit fly Drosophila melanogaster is increasingly utilized as an alternative to costly rodent models to study human diseases. Fly models exist for a wide variety of human conditions, such as Alzheimer's and Parkinson's Disease, or cardiac function. Advantages of the fly system are its rapid generation time and its low cost. However, the greatest strength of the fly system are the powerful genetic tools that allow for rapid dissection of molecular disease mechanisms. Here, we describe the diet-dependent development of metabolic phenotypes in adult fruit flies. Depending on the specific type of nutrient, as well as its relative quantity in the diet, flies show weight gain and changes in the levels of storage macromolecules. Furthermore, the activity of insulin-signaling in the major metabolic organ of the fly, the fat body, decreases upon overfeeding. This decrease in insulin-signaling activity in overfed flies is moreover observed when flies are challenged with an acute food stimulus, suggesting that overfeeding leads to insulin resistance. Similar changes were observed in aging flies, with the development of the insulin resistance-like phenotype beginning at early middle ages. Taken together, these data demonstrate that imbalanced diet disrupts metabolic homeostasis in adult D. melanogaster and promotes insulin-resistant phenotypes. Therefore, the fly system may be a useful alternative tool in the investigation of molecular mechanisms of insulin resistance and the development of pharmacologic treatment options. © 2012 Elsevier B.V. All rights reserved.
Vilaró, Senen; Palacín, Manuel; Pilch, Paul F.; Testar, Xavier; Zorzano, Antonio
INSULIN rapidly stimulates glucose use in the major target tissues, muscle and fat, by modulating a tissue-specific glucose transporter isoform1-6. Access of glucose to the target tissue is restricted by endothelial cells which line the walls of nonfenestrated capillaries of fat and muscle7. Thus, we examined whether the capillary endothelial cells are actively involved in the modulation of glucose availability by these tissues. We report here the abundant expression of the muscle/fat glucose transporter isoform in endothelial cells, using an immunocytochemical analysis with a monoclonal antibody specific for this isoform1. This expression is restricted to endothelial cells from the major insulin target tissues, and it is not detected in brain and liver where insulin does not activate glucose transport. The expression of the muscle/fat transporter isoform in endothelial cells is significantly greater than in the neighbouring muscle and fat cells. Following administration of insulin to animals in vivo, there occurs a rapid increase in the number of muscle/fat transporters present in the lumenal plasma membrane of the capillary endothelial cells. These results document that insulin promotes the translocation of the muscle/fat glucose transporter in endothelial cells. It is therefore likely that endothelial cells play an important role in the regulation of glucose use by the major insulin target tissues in normal and diseased states.
Callesen, Nicoline; Ringholm, Lene; Stage, Edna
To evaluate the insulin requirements in women with type 1 diabetes during twin pregnancy compared with singleton pregnancy.......To evaluate the insulin requirements in women with type 1 diabetes during twin pregnancy compared with singleton pregnancy....
Intensive insulin therapy: Tight blood sugar control Intensive insulin therapy can help prevent long-term diabetes complications. Consider the benefits — and understand the commitment. By Mayo Clinic ...
Marlon E Cerf
Full Text Available Beta cell dysfunction and insulin resistance are inherently complex with their interrelation for triggering the pathogenesis of diabetes also somewhat undefined. Both pathogenic states induce hyperglycemia and therefore increase insulin demand. Beta cell dysfunction results from inadequate glucose sensing to stimulate insulin secretion therefore elevated glucose concentrations prevail. Persistently elevated glucose concentrations above the physiological range result in the manifestation of hyperglycemia. With systemic insulin resistance, insulin signaling within glucose recipient tissues is defective therefore hyperglycemia perseveres. Beta cell dysfunction supersedes insulin resistance in inducing diabetes. Both pathological states influence each other and presumably synergistically exacerbate diabetes. Preserving beta cell function and insulin signaling in beta cells and insulin signaling in the glucose recipient tissues will maintain glucose homeostasis.
Gyldenløve, Mette; Storgaard, Heidi; Holst, Jens Juul
BACKGROUND: Patients with psoriasis have increased risk of type 2 diabetes. The pathophysiology is largely unknown, but it is hypothesized that systemic inflammation causes insulin resistance. Insulin sensitivity has only been sparsely investigated in patients with psoriasis, and previous studies...
Crystal M Cordes
Full Text Available Insulin-degrading enzyme (IDE is a thiol sensitive peptidase that degrades insulin and amyloid β, and has been linked to type 2 diabetes mellitus and Alzheimer's disease. We examined the thiol sensitivity of IDE using S-nitrosoglutathione, reduced glutathione, and oxidized glutathione to distinguish the effects of nitric oxide from that of the redox state. The in vitro activity of IDE was studied using either partially purified cytosolic enzyme from male Sprague-Dawley rats, or purified rat recombinant enzyme. We confirm that nitric oxide inhibits the degrading activity of IDE, and that it affects proteasome activity through this interaction with IDE, but does not affect the proteasome directly. Oxidized glutathione inhibits IDE through glutathionylation, which was reversible by dithiothreitol but not by ascorbic acid. Reduced glutathione had no effect on IDE, but reacted with partially degraded insulin to disrupt its disulfide bonds and accelerate its breakdown to trichloroacetic acid soluble fragments. Our results demonstrate the sensitivity of insulin degradation by IDE to the redox environment and suggest another mechanism by which the cell's oxidation state may contribute to the development of, and the link between, type 2 diabetes and Alzheimer's disease.
Church, Timothy J.
In Brief Patients with severe insulin resistance require >2 units/kg of body weight or 200 units/day of insulin. Yet, many patients do not achieve glycemic targets despite using very high doses of insulin. Insulin can cause weight gain, which further contributes to worsening insulin resistance. This article describes the pharmacological options for managing patients with severe insulin resistance, including the use of U-500 insulin and newer agents in combination with insulin. PMID:27092020
Chen, Yu-Min; Huang, Hui
Insulin pump is a relatively good choice for diabetic patients who require multiple daily injections with wide fluctuations of blood glucose. Patients using insulin pump therapy and still having uncontrolled blood glucose levels for various factors: insulin pump not working properly, insulin instability, insulin autoantibody, insulin allergy, etc. We described a 46-year-old woman with type 2 diabetes and progressive hyperglycemia after switching multiple daily insulin injections to insulin pu...
Bonefeld, Karen; Møller, Søren
. Patients with cirrhosis are characterised by a variety of metabolic disturbances, including nutritional and metabolic complications such as insulin resistance, malnutrition, osteopenia and hypogonadism, all related to IGF-I deficiency. The complex process of hepatic fibrogenesis and the systemic......Insulin-like growth factors (IGFs) play an essential role in growth and development, as well as in the overall cellular regulation and metabolism in the human body. In chronic liver disease, IGF levels are decreased, and the circulating levels correlate to the extent of hepatocellular dysfunction...... has a strong antifibrotic effect that acts directly through the GH/IGF system and indirectly by the regulation of hepatoprotective and profibrogenic factors. It is most likely that IGF-I deficiency contributes to the diverse metabolic complications of cirrhosis. At present, liver transplantation...
Hemmingsen, Bianca; Christensen, Louise Lundby; Wetterslev, Jørn
To compare the benefits and harms of metformin and insulin versus insulin alone as reported in randomised clinical trials of patients with type 2 diabetes.......To compare the benefits and harms of metformin and insulin versus insulin alone as reported in randomised clinical trials of patients with type 2 diabetes....
Henkin, R I
Intranasal insulin has proven useful to control hyperglycemia in diabetics but its mechanism of action has not been well defined. We attempted to understand several aspects of human insulin metabolism by measurement of and interaction of insulin and its associated moieties in nasal mucus, saliva and blood plasma under various physiological and pathological conditions. Insulin, insulin receptors, insulin-like growth factor 1 (IGF1) and insulin-like growth receptor 3 (IGFR3) were measured in nasal mucus, saliva and blood plasma in normal subjects, in thin and obese subjects and in diabetics under fasting and fed conditions. There are complex relationships among each of these moieties in each biological fluid. Insulin and its associated moieties are present in both nasal mucus and saliva. These moieties in nasal mucus and saliva report on physiological and pathological changes in glucose metabolism as do these moieties in plasma. Indeed, insulin and its associated moieties in nasal mucus may offer specific data on how insulin enters the brain and thereby play essential roles in control of insulin metabolism. These data support the concept that insulin is synthesized not only in parotid glands but also in nasal serous glands. They also support the concept that insulin enters the brain following intranasal administration either 1) by direct entry through the cribriform plate, along the olfactory nerves and into brain parenchyma, 2) by entry through specific receptors in blood-brain barrier and thereby into the brain or 3) some combination of 1) and 2). Conversely, data also show that insulin introduced directly into the brain is secreted out of brain into the peripheral circulation. Data in this study demonstrate for the first time that insulin and its associated moieties are present not only in saliva but also in nasal mucus. How these complex relationships among nasal mucus, saliva and plasma occur are unclear but results demonstrate these relationships play separate
Nowotny, Bettina; Zahiragic, Lejla; Krog, Dorothea; Nowotny, Peter J.; Herder, Christian; Carstensen, Maren; Yoshimura, Toru; Szendroedi, Julia; Phielix, Esther; Schadewaldt, Peter; Schloot, Nanette C.; Shulman, Gerald I.; Roden, Michael
Several mechanisms, such as innate immune responses via Toll-like receptor-4, accumulation of diacylglycerols (DAG)/ceramides, and activation of protein kinase C (PKC), are considered to underlie skeletal muscle insulin resistance. In this study, we examined initial events occurring during the onset of insulin resistance upon oral high-fat loading compared with lipid and low-dose endotoxin infusion. Sixteen lean insulin-sensitive volunteers received intravenous fat (iv fat), oral fat (po fat), intravenous endotoxin (lipopolysaccharide [LPS]), and intravenous glycerol as control. After 6 h, whole-body insulin sensitivity was reduced by iv fat, po fat, and LPS to 60, 67, and 48%, respectively (all P insulin sensitivity was unaffected. Muscle PKCθ activation increased by 50% after iv and po fat, membrane Di-C18:2 DAG species doubled after iv fat and correlated with PKCθ activation after po fat, whereas ceramides were unchanged. Only after LPS, circulating inflammatory markers (tumor necrosis factor-α, interleukin-6, and interleukin-1 receptor antagonist), their mRNA expression in subcutaneous adipose tissue, and circulating cortisol were elevated. Po fat ingestion rapidly induces insulin resistance by reducing nonoxidative glucose disposal, which associates with PKCθ activation and a rise in distinct myocellular membrane DAG, while endotoxin-induced insulin resistance is exclusively associated with stimulation of inflammatory pathways. PMID:23454694
James R. Krycer
Full Text Available Insulin triggers an extensive signaling cascade to coordinate adipocyte glucose metabolism. It is considered that the major role of insulin is to provide anabolic substrates by activating GLUT4-dependent glucose uptake. However, insulin stimulates phosphorylation of many metabolic proteins. To examine the implications of this on glucose metabolism, we performed dynamic tracer metabolomics in cultured adipocytes treated with insulin. Temporal analysis of metabolite concentrations and tracer labeling revealed rapid and distinct changes in glucose metabolism, favoring specific glycolytic branch points and pyruvate anaplerosis. Integrating dynamic metabolomics and phosphoproteomics data revealed that insulin-dependent phosphorylation of anabolic enzymes occurred prior to substrate accumulation. Indeed, glycogen synthesis was activated independently of glucose supply. We refer to this phenomenon as metabolic priming, whereby insulin signaling creates a demand-driven system to “pull” glucose into specific anabolic pathways. This complements the supply-driven regulation of anabolism by substrate accumulation and highlights an additional role for insulin action in adipocyte glucose metabolism.
Full Text Available Elena Matteucci,1 Ottavio Giampietro,1 Vera Covolan,2 Daniela Giustarini,3 Paolo Fanti,4 Ranieri Rossi3 1Department of Clinical and Experimental Medicine, 2Department of Chemistry and Industrial Chemistry, University of Pisa, 3Department of Life Sciences, Laboratory of Pharmacology and Toxicology, University of Siena, Siena, Italy; 4Division of Nephrology, University of Texas Health Science Center San Antonio, South Texas Veteran Health Care System, San Antonio, Texas, USA Abstract: Insulin is a life-saving medication for people with type 1 diabetes, but traditional insulin replacement therapy is based on multiple daily subcutaneous injections or continuous subcutaneous pump-regulated infusion. Nonphysiologic delivery of subcutaneous insulin implies a rapid and sustained increase in systemic insulin levels due to the loss of concentration gradient between portal and systemic circulations. In fact, the liver degrades about half of the endogenous insulin secreted by the pancreas into the venous portal system. The reverse insulin distribution has short- and long-term effects on glucose metabolism. Thus, researchers have explored less-invasive administration routes based on innovative pharmaceutical formulations, which preserve hormone stability and ensure the therapeutic effectiveness. This review examines some of the recent proposals from clinical and material chemistry point of view, giving particular attention to patients’ (and diabetologists’ ideal requirements that organic chemistry could meet. Keywords: type 1 diabetes mellitus, drug formulations, drug administration routes, insulin, portal system, nanoparticles, biodegradable polymers
Kovács, Diána; Hegedűs, Csaba; Kiss, Rita; Sári, Réka; Németh, József; Szilvássy, Zoltán; Peitl, Barna
Olanzapine, an atypical antipsychotic, can acutely induce fasting insulin resistance, but we do not know whether it is able to modulate the meal-induced insulin sensitization (MIS). Two main experimental groups (control and olanzapine-treated) were created with two subgroups (fasted and re-fed) within each. After oral vehicle/olanzapine administration, the first meal size and duration and the total amount of consumed food was recorded in conscious rats. Then, under anaesthesia, the carotid artery and jugular vein was prepared and cannulated to obtain samples for blood glucose and hormone determination as well as for insulin/glucose infusion, respectively. Basal insulin sensitivity and MIS was determined by homeostasis model assessment (HOMA) calculation and by rapid insulin sensitivity test, respectively. In fasted animals, olanzapine increased blood glucose and plasma insulin and reduced basal insulin sensitivity, but it failed to modify other hormone levels. Postprandial leptin and glucose-dependent insulinotropic polypeptide (GIP) levels increased, and ghrelin level decreased significantly (p rats. Furthermore, the MIS was preserved after acute olanzapine treatment. The blunted postprandial ghrelin and insulin response could contribute to the effect of olanzapine on feeding behaviour. Pharmacological induction of MIS may improve the olanzapine-induced insulin resistance.
Full Text Available BACKGROUND: Leucine supplementation might have therapeutic potential in preventing diet-induced obesity and improving insulin sensitivity. However, the underlying mechanisms are at present unclear. Additionally, it is unclear whether leucine supplementation might be equally efficacious once obesity has developed. METHODOLOGY/PRINCIPAL FINDINGS: Male C57BL/6J mice were fed chow or a high-fat diet (HFD, supplemented or not with leucine for 17 weeks. Another group of HFD-fed mice (HFD-pairfat group was food restricted in order to reach an adiposity level comparable to that of HFD-Leu mice. Finally, a third group of mice was exposed to HFD for 12 weeks before being chronically supplemented with leucine. Leucine supplementation in HFD-fed mice decreased body weight and fat mass by increasing energy expenditure, fatty acid oxidation and locomotor activity in vivo. The decreased adiposity in HFD-Leu mice was associated with increased expression of uncoupling protein 3 (UCP-3 in the brown adipose tissue, better insulin sensitivity, increased intestinal gluconeogenesis and preservation of islets of Langerhans histomorphology and function. HFD-pairfat mice had a comparable improvement in insulin sensitivity, without changes in islets physiology or intestinal gluconeogenesis. Remarkably, both HFD-Leu and HFD-pairfat mice had decreased hepatic lipid content, which likely helped improve insulin sensitivity. In contrast, when leucine was supplemented to already obese animals, no changes in body weight, body composition or glucose metabolism were observed. CONCLUSIONS/SIGNIFICANCE: These findings suggest that leucine improves insulin sensitivity in HFD-fed mice by primarily decreasing adiposity, rather than directly acting on peripheral target organs. However, beneficial effects of leucine on intestinal gluconeogenesis and islets of Langerhans's physiology might help prevent type 2 diabetes development. Differently, metabolic benefit of leucine supplementation
A prospective randomised cross-over study of the effect of insulin analogues and human insulin on the frequency of severe hypoglycaemia in patients with type 1 diabetes and recurrent hypoglycaemia (the HypoAna trial)
Kristensen, Peter Lommer; Pedersen-Bjergaard, Ulrik; Beck-Nielsen, Henning
of insulin analogues on glycaemic control has been documented in large trials, while their effect on the frequency of severe hypoglycaemia is less clear, especially in patients with recurrent severe hypoglycaemia. The HypoAna Trial is designed to investigate whether short-acting and long-acting insulin...... analogues in comparison with human insulin are superior in reducing the occurrence of severe hypoglycaemic episodes in patients with recurrent hypoglycaemia. This paper reports the study design of the HypoAna Trial.......Severe hypoglycaemia still represents a significant problem in insulin-treated diabetes. Most patients do not experience severe hypoglycaemia often. However, 20% of patients with type 1 diabetes experience recurrent severe hypoglycaemia corresponding to at least two episodes per year. The effect...
Simon, Airin C. R.; DeVries, J. Hans
This review presents an overview of the candidates for an improved basal insulin in the pharmaceutical pipeline. The first new basal insulin to enter the market is most likely insulin degludec (IDeg), currently reporting in phase 3 of development, from Novo Nordisk (Bagsvaerd, Denmark). IDeg has a
Volgens de gegevens uit de literatuur die in hoofdstuk 1 worden besproken, is glucose de belangrijkste prikkel voor de insuline afgifte. Na orale toediening van glucose worden hogere insuline spiegels gevonden dan na het toedienen van glucose intraverneus. Het gastric inhibitory polypeptide is van de darmhormonen, het hormaan dat de belangrijkste rol lijkt te spelen bij deze versterkte insuline afgifte. ... Zie: Samenvatting
Lipohypertrophy and lipoatrophy of injection sites was a major problem with the old impure insulins.1 The problem improved somewhat with the advent of the monocomponent bovine and porcine insulins and the current pure human insulins, such that lipoatrophy in particular is now very rare.1,2 However it now manifests ...
... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Insulin. 522.1160 Section 522.1160 Food and Drugs..., AND RELATED PRODUCTS IMPLANTATION OR INJECTABLE DOSAGE FORM NEW ANIMAL DRUGS § 522.1160 Insulin. (a) Specifications—(1) Each milliliter (mL) of porcine insulin zinc suspension contains 40 international units (IU...
Coomans, Claudia Pascalle
The studies in this thesis contribute to the understanding of the role of the brain in insulin sensitivity. We demonstrate that disturbances in circadian rhythm resulting in alterations in SCN output, can contribute to the development of insulin resistance. We also shown that insulin-stimulated
intimidating, as understanding how and when to use insulin is vital to diabetes management and ... for the insulin resistance. In the United ..... No change. 3.3 - 4.3. - 2. <3.3. - 4. *Average over 3 days. Mooradian AD et al. Ann Intern Med 2006;145:125-. 134. Table v. Titration schedule premix insulin therapy. Fasting glucose ...
Rodriguez-Rodriguez, Patricia; Sandebring-Matton, Anna; Merino-Serrais, Paula; Parrado-Fernandez, Cristina; Rabano, Alberto; Winblad, Bengt; Ávila, Jesús; Ferrer, Isidre; Cedazo-Minguez, Angel
Insulin signalling deficiencies and insulin resistance have been directly linked to the progression of neurodegenerative disorders like Alzheimer's disease. However, to date little is known about the underlying molecular mechanisms or insulin state and distribution in the brain under pathological conditions. Here, we report that insulin is accumulated and retained as oligomers in hyperphosphorylated tau-bearing neurons in Alzheimer's disease and in several of the most prevalent human tauopathies. The intraneuronal accumulation of insulin is directly dependent on tau hyperphosphorylation, and follows the tauopathy progression. Furthermore, cells accumulating insulin show signs of insulin resistance and decreased insulin receptor levels. These results suggest that insulin retention in hyperphosphorylated tau-bearing neurons is a causative factor for the insulin resistance observed in tauopathies, and describe a novel neuropathological concept with important therapeutic implications. © The Author (2017). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For Permissions, please email: email@example.com.
Chapman, M John; Sposito, Andrei C
Hypertension, a prevalent risk factor for cardiovascular disease, frequently occurs in conjunction with metabolic disturbances and in particular with dyslipidaemia; such comorbidity presents in more than one-third of hypertensive patients. Moreover, hypertension and dyslipidaemia often manifest concomitantly in the clinical context of obesity and insulin resistance. In this setting, distinct metabolic anomalies may account for the development of both conditions, and may equally act to exacerbate their effects on vascular dysfunction. Significantly, hypertension and dyslipidaemia are linked mechanistically and may act in synergy at the arterial wall to enhance atherosclerosis. In this review, we identify potential mechanisms underlying the pathophysiological interaction between hypertension and dyslipidaemia at the cellular and molecular levels, and which may underlie elevated cardiovascular risk in obesity and insulin resistance. Finally, the clinical evidence supporting the beneficial effects of an integrated pharmacotherapeutic strategy to the reduction of cardiovascular risk in patients with insulin resistance, type 2 diabetes and the metabolic syndrome is critically discussed.
Kour, Gurpreet; Masih, Updesh; Singh, Chanchal; Srivastava, Manvi; Yadav, Priti; Kushwah, Jagriti
The management of pain and anxiety in dentistry encompasses a number of procedural issues, including the delivery of anesthetic solution. One of the most important ways to manage the behavior of children is pain control. Trypanophobia is very common among dental patients and the most important goal of guidelines on behavior guidance for pediatric dental patient is to ease fear and anxiety in dental procedures in children. For the stated reasons, the purpose of the present study was to record child's pain sensation both objectively and subjectively while receiving dental local anesthesia using conventional syringes and diabetic needles. Twenty children of age group 6 to 12 years undergoing routine dental procedures participated in the study. Every child acted as one's own control, while receiving treatment on the opposite side of the same arch. Each patient was randomly assigned to receive the injection either with conventional syringe or diabetic needle for the first visit, while the injection with the other needle was administered during the second visit. Rating scales were used for objective and subjective evaluations. Statistical analysis of the measurements were made using Wilcoxon signed U test and Mann-Whitney U test which showed the mean sound, eye, motor (SEM) score difference using insulin syringe. The outcome was statistically significant when compared using the mean ranks between male and female patients with that of control group. It can be concluded that diabetic syringes exhibit clinical advantage and its use in pediatric dentistry for local anesthetics (LA) infiltration can prove beneficial. How to cite this article: Kour G, Masih U, Singh C, Srivastava M, Yadav P, Kushwah J. Insulin Syringe: A Gimmick in Pediatric Dentistry. Int J Clin Pediatr Dent 2017;10(4):319-323.
The majority of people with type 2 diabetes mellitus (T2DM) require insulin therapy to maintain HbA(1c) levels diabetes, and demonstrated a neutral effect on CV outcomes with long-term use of insulin glargine early in the course of diabetes, with a low rate of severe hypoglycaemia and modest weight gain. The EARLY, GLORY and EASIE studies also demonstrated that insulin use earlier in the treatment pathway led to improved glycaemic control, reduced weight gain and fewer hypoglycaemic episodes than when insulin was added later in the course of disease. The beneficial effect of early transient intensive insulin therapy (TIIT) at diagnosis has been demonstrated in a number of trials; it rapidly limits the damage caused by gluco- and lipotoxicity, improving residual β-cell function and potentially slowing disease progression. The evidence suggests that people newly diagnosed with T2DM and HbA(1c) > 9% should be given early TIIT to achieve normoglycaemia within weeks, after which standard care should then be adopted. Insulin use earlier in the treatment pathway should be considered, as it reduces the risk of hypoglycaemia as well as allows β-cell rest, which can help preserve β-cell function.
Copps, Kyle D.; Hançer, Nancy J.; Qiu, Wei; White, Morris F.
Constitutive activation of the mammalian target of rapamycin complex 1 and S6 kinase (mTORC1→ S6K) attenuates insulin-stimulated Akt activity in certain tumors in part through “feedback” phosphorylation of the upstream insulin receptor substrate 1 (IRS1). However, the significance of this mechanism for regulating insulin sensitivity in normal tissue remains unclear. We investigated the function of Ser-302 in mouse IRS1, the major site of its phosphorylation by S6K in vitro, through genetic knock-in of a serine-to-alanine mutation (A302). Although insulin rapidly stimulated feedback phosphorylation of Ser-302 in mouse liver and muscle, homozygous A302 mice (A/A) and their knock-in controls (S/S) exhibited similar glucose homeostasis and muscle insulin signaling. Furthermore, both A302 and control primary hepatocytes from which Irs2 was deleted showed marked inhibition of insulin-stimulated IRS1 tyrosine phosphorylation and PI3K binding after emetine treatment to raise intracellular amino acids and activate mTORC1 → S6K signaling. To specifically activate mTORC1 in mouse tissue, we deleted hepatic Tsc1 using Cre adenovirus. Although it moderately decreased IRS1/PI3K association and Akt phosphorylation in liver, Tsc1 deletion failed to cause glucose intolerance or promote hyperinsulinemia in mixed background A/A or S/S mice. Moreover, Tsc1 deletion failed to stimulate phospho-Ser-302 or other putative S6K sites within IRS1, whereas ribosomal S6 protein was constitutively phosphorylated. Following acute Tsc1 deletion from hepatocytes, Akt phosphorylation, but not IRS1/PI3K association, was rapidly restored by treatment with the mTORC1 inhibitor rapamycin. Thus, within the hepatic compartment, mTORC1 → S6K signaling regulates Akt largely through IRS-independent means with little effect upon physiologic insulin sensitivity. PMID:26846849
Martin O. Weickert
Full Text Available Insulin resistance has been proposed as the strongest single predictor for the development of Type 2 Diabetes (T2DM. Chronic oversupply of energy from food, together with inadequate physical activity, have been recognized as the most relevant factors leading to overweight, abdominal adiposity, insulin resistance, and finally T2DM. Conversely, energy reduced diets almost invariably to facilitate weight loss and reduce abdominal fat mass and insulin resistance. However, sustained weight loss is generally difficult to achieve, and distinct metabolic characteristics in patients with T2DM further compromise success. Therefore, investigating the effects of modulating the macronutrient composition of isoenergetic diets is an interesting concept that may lead to additional important insights. Metabolic effects of various different dietary concepts and strategies have been claimed, but results from randomized controlled studies and particularly from longer-term-controlled interventions in humans are often lacking. However, some of these concepts are supported by recent research, at least in animal models and short-term studies in humans. This paper provides an update of the current literature regarding the role of nutrition in the modulation of insulin resistance, which includes the discussion of weight-loss-independent metabolic effects of commonly used dietary concepts.
But, Anna; De Bruin, Marie L; Bazelier, Marloes T
AIMS/HYPOTHESIS: The aim of this work was to investigate the relationship between use of certain insulins and risk for cancer, when addressing the limitations and biases involved in previous studies. METHODS: National Health Registries from Denmark (1996-2010), Finland (1996-2011), Norway (2005-2...
Ballegooie, Evert van
In dit proefschrift worden de resultaten beschreven van een onderzoek naar: (1) de rol van bloedsuikerstrips en insuline-infusiepompjes bij de behandeling van diabetes mellitus; (2) de invloed van een verbetering van de diabetesregulatie op het verloop van de nefro-, neuro- en retinopathie en (3) de
Full Text Available Insulin resistance, ‘a relative impairment in the ability of insulin to exert its effects on glucose,protein and lipid metabolism in target tissues’, has many detrimental effects on metabolism and is strongly correlated to deposition of lipids in non-adipose tissues. Mitochondria are the main cellular sites devoted to ATP production and fatty acid oxidation. Therefore, a role for mitochondrial dysfunction in the onset of skeletal muscle insulin resistance has been proposed and many studies have dealt with possible alteration in mitochondrial function in obesity and diabetes, both in humans and animal models. Data reporting evidence of mitochondrial dysfunction in type 2 diabetes mellitus are numerous, even though the issue that this reduced mitochondrial function is causal in the development of the disease is not yet solved, also because a variety of parameters have been used in the studies carried out on this subject. By assessing the alterations in mitochondrial efficiency as well as the impact of this parameter on metabolic homeostasis of skeletal muscle cells, we have obtained results that allow us to suggest that an increase in mitochondrial efficiency precedes and therefore can contribute to the development of high-fat-induced insulin resistance in skeletal muscle.
Khan, Muhammad Tanweer; Nieuwdorp, Max; Bäckhed, Fredrik
The gut microbiota has emerged as an integral factor that impacts host metabolism and has been suggested to play a vital role in metabolic diseases such as obesity, insulin resistance, type 2 diabetes, and cardiovascular disease. In humans, cross-sectional studies have identified microbiota profiles
In this thesis we studied pathophysiological mechanisms of insulin resistance in different conditions in humans, i.e. in obesity, during lipid infusions, after hypercaloric feeding, and glucocorticoid treatment. We focused on 3 important hypotheses that are suggested to be implicated in the
ter Horst, K W; Gilijamse, P W; Koopman, K E; de Weijer, B A; Brands, M; Kootte, R S; Romijn, J A; Ackermans, M T; Nieuwdorp, M; Soeters, M R; Serlie, M J
Insulin resistance is the major contributor to cardiometabolic complications of obesity. We aimed to (1) establish cutoff points for insulin resistance from euglycemic hyperinsulinemic clamps (EHCs), (2) identify insulin-resistant obese subjects and (3) predict insulin resistance from routinely measured variables. We assembled data from non-obese (n=112) and obese (n=100) men who underwent two-step EHCs using [6,6-(2)H2]glucose as tracer (insulin infusion dose 20 and 60 mU m(-2) min(-1), respectively). Reference ranges for hepatic and peripheral insulin sensitivity were calculated from healthy non-obese men. Based on these reference values, obese men with preserved insulin sensitivity or insulin resistance were identified. Cutoff points for insulin-mediated suppression of endogenous glucose production (EGP) and insulin-stimulated glucose disappearance rate (Rd) were 46.5% and 37.3 μmol kg(-)(1) min(-)(1), respectively. Most obese men (78%) had EGP suppression within the reference range, whereas only 12% of obese men had Rd within the reference range. Obese men with Rd insulin-sensitive obese men in age, body mass index (BMI), body composition, fasting glucose or cholesterol, but did have higher fasting insulin (110±49 vs 63±29 pmol l(-1), Pinsulin resistance (HOMA-IR) (4.5±2.2 vs 2.7±1.4, P=0.004). Insulin-resistant obese men could be identified with good sensitivity (80%) and specificity (75%) from fasting insulin >74 pmol l(-1). Most obese men have hepatic insulin sensitivity within the range of non-obese controls, but below-normal peripheral insulin sensitivity, that is, insulin resistance. Fasting insulin (>74 pmol l(-1) with current insulin immunoassay) may be used for identification of insulin-resistant (or metabolically unhealthy) obese men in research and clinical settings.
Full Text Available Controlled release systems for insulin are frequent subjects of research, because it is rapidly degraded by proteolytic enzymes in the gastrointestinal tract and minimally absorbed after oral administration. Controlled release systems also provide significant contribution to its stability. Different techniques are used for the preparation of drug-loaded nanoparticles, and many novel techniques are being developed. The size and morphology of insulin-loaded nanoparticles may vary according to performed techniques, even if the same polymer is used. The aim of this study was to demonstrate the cytotoxicity of insulin loaded nanoparticles and the effect of various synthesis parameters on the particle size, polydispersity index (PdI, loading efficiency, and particle morphology. In the experiments, poly(lactic-co-glycolic acid (PLGA and insulin-loaded PLGA nanoparticles were prepared using the double emulsion (w/o/w method. The characterization of the nanoparticles were performed with a UV spectrometer, the Zeta-sizer system, FTIR spectroscopy, and a scanning probe microscope. Cell toxicity of different concentrations was assayed with MTT methods on L929 fibroblast cells. The optimum size of the insulin-loaded PLGA nanoparticle was obtained with a 96.5% encapsulation efficiency, a 224.5 nm average particle size, and a 0.063 polydispersity index. This study obtained and characterized spherical morphology, determined that the nanoparticles have very low toxicity, and showed the effect of different parameters on particle size and polydispersity. DOI: http://dx.doi.org/10.17807/orbital.v9i1.934
Morton, N.M.; Emilsson, V.; Groot, R.P. de; Pallett, A.L.; Cawthorne, M.A.
Leptin is a cytokine secreted from adipose tissue at a rate commensurate with the size of the body's fat stores. In addition to its anorectic and thermogenic central actions, leptin is known to act on peripheral tissues, including the pancreatic ß-cell where it inhibits insulin secretion and
Bertuzzi, Federico; Pintaudi, Basilio; Bonomo, Matteo; Garuti, Fabio
Unintended pump insulin delivery was reported to occur as a consequence of decreased atmospheric pressure, probably mediated by air bubble formation and the expansion of existing bubbles. This observation has been used to explain some hypoglycemic episodes occurring in patients on insulin pump treatment in between 1 and 1 h 45 min after the flight takeoff. New models of insulin pumps have been introduced in the market, most of them are waterproof certified. It is not clear if in these new pumps the influence of atmospheric pressure changes on the insulin delivery is still present. Moreover, there are no evidences related to the insulin pump operations in hyperbaric conditions, like as during diving activities. Our aim is therefore to verify the eventual variation of insulin pump delivery determined by atmospheric pressure changes in hyperbaric conditions. Three new models of insulin pumps were tested in hyperbaric conditions at a flow rate of 2 U/h. Atmospheric pressure variation affected pump insulin release. An increase in the atmospheric pressure from 1 to 1.3 atmosphere (ATA) induced a decrease of pump basal insulin release (about -0.2 U/10 min); conversely, when the atmospheric pressure returned from 1.3 to 1 ATA, an unintended insulin delivery was observed (about +0.3 U/10 min). This phenomenon appeared to be independent of the insulin pump rate and dependent on the presence of air bubbles within the insulin tube setting and cartridge. Unintended insulin delivery driven by atmospheric pressure changes in hyperbaric conditions occurred in the new insulin pumps available. Patients should pay attention to possible variation of insulin rate during the flight or during diving activities.
Rathmann, Wolfgang; Czech, Marcin; Franek, Edward; Kostev, Karel
To compare short-term basal insulin therapy persistence and its predictors in Poland and Germany. Persistence was defined as proportions of patients remaining on the initial basal insulin (analogs: Poland: n = 6,889, Germany: n = 454,067; neutral protamine Hagedorn (NPH) insulins: Poland: n = 50,761, Germany: n = 226,064) over 2 years based on nationwide prescription databases (LRx; IMS Health) in Poland and Germany from 2013 to 2015. Persistence was evaluated by Kaplan-Meier curves (log-rank tests). Risk of discontinuation of initial basal insulin was investigated using Cox regression models adjusting for age, sex, comedication with other glucose-lowering agents and baseline or comedication with antihypertensives, lipid-lowering drugs, antidepressants, and antiepileptics. In Poland, 2-year persistence was 83.0% in analog insulin and 73.3% in NPH users (p Germany, persistence was also higher in patients with analog insulins (92.6% vs. 79.0%; p Germany: 0.27 (0.27 - 0.28)). Higher age (> 75 vs. ≤ 60 years: Poland: 1.24 (1.16 - 1.33), Germany: 1.09 (1.07 - 1.11)) and GLP-1 receptor agonist use (Poland: 2.76 (1.38 - 5.53), Germany: 1.21 (1.16 - 1.26)) were related to higher risk of discontinuation. Male sex, metformin, sulfonylurea, thiazolidinedione, and short-acting insulin prescriptions as well as antihypertensive, anti-epileptic, and lipid-lowering drug use were associated with lower risk of discontinuation in both countries (all p Germany treatment persistence of newly-prescribed basal insulin is influenced by type of insulin (analog vs. NPH) and by glucose-lowering and other comedications. .
Shree, Nitya; Bhonde, Ramesh R
The link between insulin resistance (IR) and type 2 diabetes has been recognized for a long time. Type 2 diabetes is often associated with basal hyperinsulinemia, reduced sensitivity to insulin, and disturbances in insulin release. There are evidences showing the reversal of IR by mesenchymal stem cells. However, the effect of conditioned media from adipose derived mesenchymal stem cells (ADSCs-CM) in reversal of IR has not been established. We established an insulin resistant model of 3T3L1 and C2C12 cells and treated with ADSCs-CM. 2-NBDG (2-[N-[7-Nitrobenz-2-oxa-1,3-diazol-4-yl]Amino]-2-Deoxyglucose) uptake was performed to assess improvement in glucose uptake. Genes involved in glucose transport and in inflammation were also analysed. Western blot for glucose transporter-4 and Akt was performed to evaluate translocation of Glut4 and insulin signaling respectively. We found that the ADSCs-CM treated cells restored insulin, stimulated glucose uptake as compared to the untreated control indicating the insulin sensitizing effect of the CM. The treated cells also showed inhibition adipogenesis in 3T3L1 cells and significant reduction of intramuscular triglyceride accumulation in C2C12 cells. Gene expressions studies revealed the drastic upregulation of GLUT4 gene and significant reduction in IL6 and PAI1 gene in both 3T3L1 and C2C12 cells, indicating possible mechanism of glucose uptake with concomitant decrease in inflammation. Enhancement of GLUT4 and phospho Akt protein expression seems to be responsible for the increment in glucose uptake and enhanced insulin signaling, respectively. Our study revealed for the first time that ADSCs-CM acts as an alternative insulin sensitizer providing stem cell solution to IR. J. Cell. Biochem. 118: 2037-2043,2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.
Chung, Li Hung C.; Birch, David J. S.; Vyshemirsky, Vladislav; Ryadnov, Maxim G.; Rolinski, Olaf J.
Time-resolved emission spectra (TRES) have been used to detect conformational changes of intrinsic tyrosines within bovine insulin at a physiological pH. The approach offers the ability to detect the initial stages of insulin aggregation at the molecular level. The data analysis has revealed the existence of at least three fluorescent species undergoing dielectric relaxation and significant spectral changes due to insulin aggregation. The results indicate the suitability of the intrinsic TRES approach for insulin studies and for monitoring its stability during storage and aggregation in insulin delivery devices.
Mudry, Jonathan M; Lassiter, David G; Nylén, Carolina
of selected genes was determined in muscle from healthy and type 2 diabetic men before and after a glucose tolerance test. Insulin altered DNA methylation in the 3'UTR of the calcium pump ATP2A3 gene. Insulin increased DNA methylation in the gene body of DAPK3, a gene involved in cell proliferation, apoptosis......DNA methylation is altered by environmental factors. We hypothesized DNA methylation is altered in skeletal muscle in response to either insulin or glucose exposure. We performed a genome-wide DNA methylation analysis in muscle from healthy men before and after insulin exposure. DNA methylation...... glucose incorporation to glycogen was unaltered by siRNA against DAPK3, palmitate oxidation was increased. In conclusion, insulin and glucose exposure acutely alter the DNA methylation profile of skeletal muscle, indicating DNA methylation constitutes a rapidly and adaptive epigenetic mark. Furthermore...
Dela, Flemming; Stallknecht, B.; Biering-Sørensen, Fin
concentrations in arterial plasma and in the dialysate (reflecting extracellular fluid) did not change in response to insulin in either group, but increased in response to suprapubic bladder tapping in the SCI. Potassium balance measured by microdialysis shifted from a net release to a net uptake in response...... nervous activity. The vasodilatation seen in response to hyperinsulinemia is a locally acting mechanism. People with SCI are markedly insulin resistant compared with able-bodied individuals....
Obesity increases the risk for type 2 diabetes through induction of insulin resistance. Treatment of type 2 diabetes has been limited by little translational knowledge of insulin resistance although there have been several well-documented hypotheses for insulin resistance. In those hypotheses, inflammation, mitochondrial dysfunction, hyperinsulinemia and lipotoxicity have been the major concepts and have received a lot of attention. Oxidative stress, endoplasmic reticulum (ER) stress, genetic background, aging, fatty liver, hypoxia and lipodystrophy are active subjects in the study of these concepts. However, none of those concepts or views has led to an effective therapy for type 2 diabetes. The reason is that there has been no consensus for a unifying mechanism of insulin resistance. In this review article, literature is critically analyzed and reinterpreted for a new energy-based concept of insulin resistance, in which insulin resistance is a result of energy surplus in cells. The energy surplus signal is mediated by ATP and sensed by adenosine monophosphate-activated protein kinase (AMPK) signaling pathway. Decreasing ATP level by suppression of production or stimulation of utilization is a promising approach in the treatment of insulin resistance. In support, many of existing insulin sensitizing medicines inhibit ATP production in mitochondria. The effective therapies such as weight loss, exercise, and caloric restriction all reduce ATP in insulin sensitive cells. This new concept provides a unifying cellular and molecular mechanism of insulin resistance in obesity, which may apply to insulin resistance in aging and lipodystrophy.
Kim, Hakjoong; Kalkhoff, Ronald K.; Costrini, Nicholas V.; Cerletty, James M.; Jacobson, Mitchell
Plasma insulin dynamics were evaluated in 10 patients with primary hyperparathyroidism before and after parathyroidectomy and correction of hypercalcemia. Before surgery fasting plasma insulin concentrations and insulin responses to administered glucose, tolbutamide, and glucagon were significantly greater than postoperative values. Hyperinsulinemia was not associated with altered glucose curves during glucose or glucagon tolerance tests, but a relatively greater insulin response to tolbutamide resulted in an increased hypoglycemic effect following its administration. The glucose-lowering action of intravenous insulin was slightly impaired before treatment. Intramuscular injections of parathormone to six normal men for 8 days induced mild hypercalcemia and hypophosphatemia and reproduced augmented plasma insulin responses to oral glucose and intravenous tolbutamide. 4-hr intravenous infusions of calcium to another group of six normal men raised serum calcium concentrations above 11 mg/100 ml. This did not alter glucose or insulin curves during oral glucose tolerance but markedly accentuated insulin responses to tolbutamide and potentiated its hypoglycemic effect. When highly purified parathormone was incubated with isolated pancreatic islets of male rats, glucose-stimulated insulin secretion was unaffected. These findings suggest that chronic hypercalcemia of hyperparathyroidism sustains a form of endogenous insulin resistance that necessitates augmented insulin secretion to maintain plasma glucose homeostasis. This state is insufficient to oppose tolbutamide-induced hypoglycemia because of an additional direct, selective enhancement of hypercalcemia on pancreatic beta cell responsiveness to the sulfonylurea. The possible direct role of parathormone in these events has not been established. PMID:5129311
Horita, Shoko; Nakamura, Motonobu; Suzuki, Masashi; Satoh, Nobuhiko; Suzuki, Atsushi; Seki, George
Insulin resistance has been characterized as attenuation of insulin sensitivity at target organs and tissues, such as muscle and fat tissues and the liver. The insulin signaling cascade is divided into major pathways such as the PI3K/Akt pathway and the MAPK/MEK pathway. In insulin resistance, however, these pathways are not equally impaired. For example, in the liver, inhibition of gluconeogenesis by the insulin receptor substrate (IRS) 2 pathway is impaired, while lipogenesis by the IRS1 pathway is preserved, thus causing hyperglycemia and hyperlipidemia. It has been recently suggested that selective impairment of insulin signaling cascades in insulin resistance also occurs in the kidney. In the renal proximal tubule, insulin signaling via IRS1 is inhibited, while insulin signaling via IRS2 is preserved. Insulin signaling via IRS2 continues to stimulate sodium reabsorption in the proximal tubule and causes sodium retention, edema, and hypertension. IRS1 signaling deficiency in the proximal tubule may impair IRS1-mediated inhibition of gluconeogenesis, which could induce hyperglycemia by preserving glucose production. In the glomerulus, the impairment of IRS1 signaling deteriorates the structure and function of podocyte and endothelial cells, possibly causing diabetic nephropathy. This paper mainly describes selective insulin resistance in the kidney, focusing on the proximal tubule. PMID:27247938
Obesity increases the risk for type 2 diabetes through induction of insulin resistance. Treatment of type 2 diabetes has been limited by little translational knowledge of insulin resistance although there have been several well-documented hypotheses for insulin resistance. In those hypotheses, inflammation, mitochondrial dysfunction, hyperinsulinemia and lipotoxicity have been the major concepts and have received a lot of attention. Oxidative stress, endoplasmic reticulum (ER) stress, genetic background, aging, fatty liver, hypoxia and lipodystrophy are active subjects in the study of these concepts. However, none of those concepts or views has led to an effective therapy for type 2 diabetes. The reason is that there has been no consensus for a unifying mechanism of insulin resistance. In this review article, literature is critically analyzed and reinterpreted for a new energy-based concept of insulin resistance, in which insulin resistance is a result of energy surplus in cells. The energy surplus signal is mediated by ATP and sensed by adenosine monophosphate-activated protein kinase (AMPK) signaling pathway. Decreasing ATP level by suppression of production or stimulation of utilization is a promising approach in the treatment of insulin resistance. In support, many of existing insulin sensitizing medicines inhibit ATP production in mitochondria. The effective therapies such as weight loss, exercise, and caloric restriction all reduce ATP in insulin sensitive cells. This new concept provides a unifying cellular and molecular mechanism of insulin resistance in obesity, which may apply to insulin resistance in aging and lipodystrophy. PMID:23471659
Penhoat, A; Chatelain, P G; Jaillard, C; Saez, J M
hydroxylases. These results indicate that both IGF-I and insulin, acting through their own receptor, play an important role in the maintenance of specific adrenal cell functions. However, at physiological concentrations IGF-I is more potent than insulin.
Narayan, Roger J
Treatment of insulin-dependent diabetes mellitus, also known as Type 1 diabetes mellitus, requires delivery of exogenous insulin via injection or pump. An alternative to syringe-based subcutaneous delivery of insulin involves use of microneedles. These delivery of insulin. Benefits associated with microneedle-based delivery of insulin include minimal training for use, painless insertion, as well as the potential to combine microneedles with sensors and drug delivery devices to create an autonomous artificial pancreas. In this review, the efforts of academic and industrial researchers over the past decade to examine the functionality of microneedles for delivery of insulin, including insulin-containing nanomaterials, via in vitro, ex vivo, and in vivo studies are considered.
Muhammad A. Abdul-Ghani
Full Text Available Insulin resistance in skeletal muscle is manifested by decreased insulin-stimulated glucose uptake and results from impaired insulin signaling and multiple post-receptor intracellular defects including impaired glucose transport, glucose phosphorylation, and reduced glucose oxidation and glycogen synthesis. Insulin resistance is a core defect in type 2 diabetes, it is also associated with obesity and the metabolic syndrome. Dysregulation of fatty acid metabolism plays a pivotal role in the pathogenesis of insulin resistance in skeletal muscle. Recent studies have reported a mitochondrial defect in oxidative phosphorylation in skeletal muscle in variety of insulin resistant states. In this review, we summarize the cellular and molecular defects that contribute to the development of insulin resistance in skeletal muscle.
Full Text Available Background. The well-defined program of the insulin therapy is a guarantee of efficient treatment of a patient with the diabetic ketoacidosis. The approaches to the treatment varied depending on the gained experience, however, the experts’ opinions about the dose and methods of the insulin therapy are still ambiguous. The evaluation of the insulin therapy efficacy via continuous infusion by means of a syringe pump with the initial dose 0.1 unit/kg/h under the control of the glycemia without the usage of a bolus insulin dose IV and the determination of the necessary daily insulin dose on the first day of the diabetic ketoacidosis treatment. The purpose of the study — the evaluation of the insulin therapy efficacy for the diabetic ketoacidosis with syringe pump by means of the continuous infusion with the initial dose 0.1 unit/kg/h under the control of the glycemia as the principal component of the pathogenetic treatment and the determination of the necessary daily insulin dose on the first day of the diabetic ketoacidosis treatment in parallel with the rehydration start by means of physiological solution. Materials and methods. 55 patients with diabetic ketoacidosis aged from 9 to 65 years were examined. The average age of the patients was 31.58 ± 17.18 years. The specific weight of the female patients was 56 %, and male patients — 44 %. 80 % of patients had the type 1 diabetes mellitus. The determination of the glucose level was carried out in the capillary blood by means of the automatic glucose analyzer. For all the patients the glycemia was controlled in an hour after the injection of 0.1 unit/kg/h of insulin and then the dose was corrected in case of necessity with the control of the glucose level. For the treatment the fast-acting insulin was used and analogues of ultra fast-acting insulins, their total dose was calculated during the first day of treatment. Results. The glycemia level during the hospitalization fluctuated
Khristov, V; Manov, A
Human insulin was applied to three insulin resistant diabetic patients with moderate insulin needs of 1.9 U/kg body mass/24 hours. The mean level of the insulin antibodies was 61%. In all three patients biostator control was carried out before beginning the treatment with human insulin. After an 8 month treatment a satisfactory compensation of diabetes was achieved with an average insulin dose of 1.02 U/kg body mass, a considerable lowering of the mean blood sugar level and a reduction of the glycosilated hemoglobin examined in two of the patients. At the end of the 8 month period the level of the insulin antibodies was considerably lowered in all three patients. The advantage of human insulin as an alternative for the treatment of immunologic insulin resistance is pointed out.
Ohguni, S; Notsu, K; Tanaka, J; Sato, T; Kato, Y
Glucose-induced insulin secretion, 24-h urinary C-peptide (CPR) and euglycemic clamp were examined in five patients with hyperthyroid Graves' disease before and 2 weeks after treatment with arotinolol (20 mg/day, p.o.). Plasma glucose and insulin responses to oral administration of 75 g glucose were not changed by arotinolol treatment. 24-h urinary CPR and basal posthepatic insulin delivery rate (BPIDR) as an indicator of insulin secretion were significantly suppressed by arotinolol. Glucose infusion rate (GIR) as an indicator of insulin sensitivity and glucose clearance rate (GCR) were not influenced by arotinolol therapy. Insulin clearance rate (ICR) was significantly suppressed by arotinolol. These findings suggest that arotinolol inhibits insulin secretion by decreasing ICR but does not attenuate insulin release induced by glucose in hyperthyroid patients, and that insulin sensitivity and GCR are not affected by arotinolol.
Nicole M. Templeman
Full Text Available The causal relationships between insulin levels, insulin resistance, and longevity are not fully elucidated. Genetic downregulation of insulin/insulin-like growth factor 1 (Igf1 signaling components can extend invertebrate and mammalian lifespan, but insulin resistance, a natural form of decreased insulin signaling, is associated with greater risk of age-related disease in mammals. We compared Ins2+/− mice to Ins2+/+ littermate controls, on a genetically stable Ins1 null background. Proteomic and transcriptomic analyses of livers from 25-week-old mice suggested potential for healthier aging and altered insulin sensitivity in Ins2+/− mice. Halving Ins2 lowered circulating insulin by 25%–34% in aged female mice, without altering Igf1 or circulating Igf1. Remarkably, decreased insulin led to lower fasting glucose and improved insulin sensitivity in aged mice. Moreover, lowered insulin caused significant lifespan extension, observed across two diverse diets. Our study indicates that elevated insulin contributes to age-dependent insulin resistance and that limiting basal insulin levels can extend lifespan.
Morcavallo, Alaide; Genua, Marco; Palummo, Angela; Kletvikova, Emilia; Jiracek, Jiri; Brzozowski, Andrzej M.; Iozzo, Renato V.; Belfiore, Antonino; Morrione, Andrea
The insulin receptor isoform A (IR-A) binds both insulin and insulin-like growth factor (IGF)-II, although the affinity for IGF-II is 3–10-fold lower than insulin depending on a cell and tissue context. Notably, in mouse embryonic fibroblasts lacking the IGF-IR and expressing solely the IR-A (R−/IR-A), IGF-II is a more potent mitogen than insulin. As receptor endocytosis and degradation provide spatial and temporal regulation of signaling events, we hypothesized that insulin and IGF-II could affect IR-A biological responses by differentially regulating IR-A trafficking. Using R−/IR-A cells, we discovered that insulin evoked significant IR-A internalization, a process modestly affected by IGF-II. However, the differential internalization was not due to IR-A ubiquitination. Notably, prolonged stimulation of R−/IR-A cells with insulin, but not with IGF-II, targeted the receptor to a degradative pathway. Similarly, the docking protein insulin receptor substrate 1 (IRS-1) was down-regulated after prolonged insulin but not IGF-II exposure. Similar results were also obtained in experiments using [NMeTyrB26]-insulin, an insulin analog with IR-A binding affinity similar to IGF-II. Finally, we discovered that IR-A was internalized through clathrin-dependent and -independent pathways, which differentially regulated the activation of downstream effectors. Collectively, our results suggest that a lower affinity of IGF-II for the IR-A promotes lower IR-A phosphorylation and activation of early downstream effectors vis à vis insulin but may protect IR-A and IRS-1 from down-regulation thereby evoking sustained and robust mitogenic stimuli. PMID:22318726
Menting, John G.; Whittaker, Jonathan; Margetts, Mai B.; Whittaker, Linda J.; Kong, Geoffrey K.-W.; Smith, Brian J.; Watson, Christopher J.; Žáková, Lenka; Kletvíková, Emília; Jiráček, Jiří; Chan, Shu Jin; Steiner, Donald F.; Dodson, Guy G.; Brzozowski, Andrzej M.; Weiss, Michael A.; Ward, Colin W.; Lawrence, Michael C.
Insulin receptor signalling has a central role in mammalian biology, regulating cellular metabolism, growth, division, differentiation and survival1,2. Insulin resistance contributes to the pathogenesis of type 2 diabetes mellitus and the onset of Alzheimer’s disease3; aberrant signalling occurs in diverse cancers, exacerbated by crosstalk with the homologous type 1 insulin-like growth factor receptor (IGF1R)4. Despite more than three decades of investigation, the three-dimensional structure of the insulin–insulin receptor complex has proved elusive, confounded by the complexity of producing the receptor protein. Here we present the first view, to our knowledge, of the interaction of insulin with its primary binding site on the insulin receptor, on the basis of four crystal structures of insulin bound to truncated insulin receptor constructs. The direct interaction of insulin with the first leucine-rich-repeat domain (L1) of insulin receptor is seen to be sparse, the hormone instead engaging the insulin receptor carboxy-terminal α-chain (αCT) segment, which is itself remodelled on the face of L1 upon insulin binding. Contact between insulin and L1 is restricted to insulin B-chain residues. The αCT segment displaces the B-chain C-terminal β-strand away from the hormone core, revealing the mechanism of a long-proposed conformational switch in insulin upon receptor engagement. This mode of hormone–receptor recognition is novel within the broader family of receptor tyrosine kinases5. We support these findings by photo-crosslinking data that place the suggested interactions into the context of the holoreceptor and by isothermal titration calorimetry data that dissect the hormone–insulin receptor interface. Together, our findings provide an explanation for a wealth of biochemical data from the insulin receptor and IGF1R systems relevant to the design of therapeutic insulin analogues. PMID:23302862
of pregnancy and possibly NEFA metabolism, may act to maintain a reduced insulin output, thereby sparing glucose for non-insulin dependent placental uptake and ultimately, fetal requirements.
Schreiber, Stephan A; Russmann, Anika
To investigate the effect of initiating insulin glargine (glargine: LANTUS), a once-daily basal insulin analogue, plus an educational programme, on glycaemic control and body weight in patients with type 1 diabetes in clinical practice. A retrospective analysis of the medical records of 65 patients (mean age: 40.7 +/- 13.3 years) with type 1 diabetes was performed. Patients had previously been treated with NPH insulin (NPH; n = 54) or NPH insulin + lente insulin (NPH + lente; n = 11) and then received glargine once daily (bedtime), plus short-acting prandial insulin, for 30 months. Before initiation of glargine, patients participated in a diabetes educational programme and then received physician consultations throughout the study. Metabolic control, body weight and severe hypoglycaemia data were analysed at 9 and 30 months. Following initiation of glargine, patients showed a decrease in HbA(1c) from 7.29 +/- 1.1% to 7.06 +/- 1.0%; p weight was observed in the overall group. No episodes of severe hypoglycaemia (blood glucose weight gain versus previous treatment with NPH insulin or insulin lente. Further studies in a larger cohort of patients would help to confirm these results.
Randomized clinical trial of the efficacy and safety of insulin glargine vs. NPH insulin as basal insulin for the treatment of glucocorticoid induced hyperglycemia using continuous glucose monitoring in hospitalized patients with type 2 diabetes and respiratory disease.
Ruiz de Adana, María S; Colomo, Natalia; Maldonado-Araque, Cristina; Fontalba, María I; Linares, Francisca; García-Torres, Francisca; Fernández, Rosario; Bautista, Carmen; Olveira, Gabriel; de la Cruz, José L; Rojo-Martínez, Gemma; Valdés, Sergio
To investigate the clinical efficacy and safety of insulin glargine compared with NPH insulin as basal insulin for the management of corticosteroid-induced hyperglycemia in hospitalized people with type 2 diabetes (T2DM) and respiratory disease. Randomized, two-arm parallel group, clinical trial undertaken from February 2011 to November 2012 on the pneumology ward of the Hospital Regional Universitario de Málaga (Spain), involving 53 participants with T2DM treated with medium/high doses of intermediate-acting corticosteroids. Participants were randomly assigned to receive one single dose of insulin glargine or NPH insulin in three equally divided doses before each meal as basal insulin within a basal-bolus insulin protocol. The intervention lasted six days or until discharge if earlier. No significant differences were seen between groups during the study in mean blood glucose (11.43±3.44 mmol/l in glargine vs. 11.88±2.94 mmol/l in NPH, p=0.624), and measures of glucose variability (standard deviation 3.27±1.16 mmol/l vs. 3.61±0.99 mmol/l, p=0.273; coefficient of variation 1.55±0.33 mmol/l vs. 1.72±0.39 mmol/l, p=0.200). Results from CGM were concordant with those obtained with capillary blood glucose reading. The length of hospital stay was also similar between groups (8.2±2.8 days vs. 9.8±3.4 days, p=0.166) There was a non significant trend for lower episodes of mild (4 vs. 8, p=0.351) and severe hypoglycemia (0 vs. 3, p=0.13) in the glargine group. The results of this study showed that insulin glargine and NPH insulin are equally effective in a basal-bolus insulin protocol to treat glucocorticoid-induced hyperglycemia in people with T2DM on a pneumology ward. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
Full Text Available In medical practice, almost every clinician may encounter patients with skin disease. However, it is not always easy for physicians of all specialties to face the daily task of determining the nature and clinical implication of dermatologic manifestations. Are they confined to the skin, representing a pure dermatologic event? Or are they also markers of internal conditions relating to the patient’s overall health? In this review, we will discuss the principal cutaneous conditions which have been linked to metabolic alterations. Particularly, since insulin has an important role in homeostasis and physiology of the skin, we will focus on the relationships between insulin resistance (IR and skin diseases, analyzing strongly IR-associated conditions such as acanthosis nigricans, acne, and psoriasis, without neglecting emerging and potential scenarios as the ones represented by hidradenitis suppurativa, androgenetic alopecia, and hirsutism.
Full Text Available The central nervous system (CNS controls vital functions, by efficiently coordinating peripheral and central cascades of signals and networks in a coordinated manner. Historically, the brain was considered to be an insulin-insensitive tissue. But, new findings demonstrating that insulin is present in different regions of themammalian brain, in particular the hypothalamus and the hippocampus. Insulin acts through specific receptors and dialogues with numerous peptides, neurotransmitters and adipokines such as leptin. The cross-talk between leptin and insulin signaling pathways at the hypothalamic level is clearly involved in the control of energy homeostasis. Both hormones are anorexigenic through their action on hypothalamic arcuate nucleus by inducing the expression of anorexigenic neuropetides such as POMC (pro-opiomelanocortin, the precursor of aMSH and reducing the expression of orexigenic neuropeptide such as NPY (Neuropeptide Y. Central defect of insulin and leptin signaling predispose to obesity (leptin-resistant state and type-2 diabetes (insulin resistant state. Obesity and type-2 diabetes are associated to deep alterations in energy homeostasis control but also to other alterations of CNS functions as the predisposition to neurodegenerative diseases such as Alzheimer’s disease (AD. AD is a neurodegenerative disorder characterized by distinct hallmarks within the brain. Postmortem observation of AD brains showed the presence of parenchymal plaques due to the accumulation of the amyloid beta (AB peptide and neurofibrillary tangles. These accumulations result from the hyperphosphorylation of tau (a mictrotubule-interacting protein. Both insulin and leptin have been described to modulate tau phosphorylation and therefore in leptin and insulin resistant states may contribute to AD. The concentrations of leptin and insulin cerebrospinal fluid are decreased type2 diabetes and obese patients. In addition, the concentration of insulin in the
The Results of Open-Label, Multicenter, Non-Randomized Study on the Efficacy and Safety of Insulins: Insuman Basal®, Insuman Comb 25®, Insuman Rapid® in Patients with Diabetes Mellitus Type 2 Who Underwent Basic Training in Diabetes Schools (SPIRIT
Conclusions. Treatment with Insuman® insulins of patients with DM-2, who were not compensated while taking OADs, was associated with improved glycemic control without an increase in the incidence of severe hypoglycemia. There was no statistically significant increase in the effectiveness of therapy in patients, who have successfully completed a training program at diabetes school, compared with evaluation of overall efficiency. The state of young studied population of patients with inadequate control at baseline, and those who had developed cardiovascular complications associated with DM, improved in most cases in terms of glycemic control, and, at that, episodes of severe hypoglycemia were not detected. This may be due to the positive influence of training in diabetes school.
Noura eEl Khoury
Full Text Available The neuropathological hallmarks of Alzheimer's disease (AD include senile plaques of β-amyloid (Aβ peptides (a cleavage product of the Amyloid Precursor Protein, or APP and neurofibrillary tangles (NFT of hyperphosphorylated Tau protein assembled in paired helical filaments (PHF. NFT pathology is important since it correlates with the degree of cognitive impairment in AD.Only a small proportion of AD is due to genetic variants, whereas the large majority of cases (~99% is late onset and sporadic in origin. The cause of sporadic AD is likely to be multifactorial, with external factors interacting with biological or genetic susceptibilities to accelerate the manifestation of the disease.Insulin dysfunction, manifested by diabetes mellitus (DM might be such factor, as there is extensive data from epidemiological studies suggesting that DM is associated with an increased relative risk for AD. Type 1 diabetes (T1DM and type 2 diabetes (T2DM are known to affect multiple cognitive functions in patients. In this context, understanding the effects of diabetes on Tau pathogenesis is important since tau pathology show a strong relationship to dementia in AD, and to memory loss in normal aging and mild cognitive impairment.Here, we reviewed preclinical studies that link insulin dysfunction to Tau protein pathogenesis, one of the major pathological hallmarks of AD. We found more than 30 studies reporting on Tau phosphorylation in a mouse or rat model of insulin dysfunction. We also payed attention to potential sources of artifacts, such as hypothermia and anesthesia, that were demonstrated to results in Tau hyperphosphorylation and could major confounding experimental factors. We found that very few studies reported the temperature of the animals, and only a handful did not use anesthesia. Overall, most published studies showed that insulin dysfunction can promote Tau hyperphosphorylation and pathology, both directly and indirectly, through hypothermia.
Woo, Vincent C
The treatment of type 1 diabetes mellitus (T1DM) and type 2 diabetes mellitus (T2DM) using insulin is not ideal at this time. Despite advances made with basal insulin analogues, many individuals achieve less than optimal glycemic control or are at risk for hypoglycemia. Currently available basal insulin analogues do not deliver steady, peakless, continuous insulin for >24 hours and are associated with adverse events, including hypoglycemia. The objective of this paper was to review the clinical efficacy and safety of upcoming long-acting insulin analogues such as insulin degludec and insulin glargine 300 U/mL (Gla-300). A comprehensive literature search of PubMed and Google Scholar was conducted from 1966 to 2015. The search included randomized controlled trials that specifically assessed the efficacy and safety of insulin degludec and Gla-300 in patients with T1DM and T2DM. The efficacy of insulin degludec and Gla-300 in achieving glycemic control has been reported in clinical trials in adults with T1DM and T2DM. Not only did a large number of patients succeed in meeting glycosylated hemoglobin targets, but they also experienced reductions in hypoglycemic events. These 2 therapies are associated with a reduced risk of nocturnal hypoglycemia and are generally well tolerated. The long-acting insulin analogues insulin degludec and Gla-300 are promising therapies in the treatment of T1DM and T2DM. Their improved insulin delivery for >24 hours offers glycemic control with a good safety profile. Copyright © 2017 Elsevier HS Journals, Inc. All rights reserved.
Vähätalo, Markku A; Viikari, Jorma; Rönnemaa, Tapani
Our aim was to compare the effects of an intermediate acting human insulin (NPH) and a long-acting insulin analog, insulin glargine, in insulin naïve type 2 diabetes patients, stratified by the type of hyperglycemia (fasting or postprandial type). Based on different action profiles, we hypothesized that patients having different hyperglycemia types would react differently when treated with these insulins. This is a post hoc analysis of the Lanmet study data. The Lanmet study was a randomized, 36-week controlled insulin initiation study in type 2 diabetes patients. 109 subjects with baseline HbA1c >8.0% (64 mmol/mol) completed the study. The patients were divided into two groups according to fasting glucose (mmol/l)/HbA1c (%) ratio. Patients with a ratio ≥1.3 were defined as having fasting type and those with a ratio weight, and final insulin dose. Independently of insulin type, compared to patients with postprandial type hyperglycemia, those with fasting type hyperglycemia had 2.1 kg/m(2) greater initial BMI (p = 0.044), gained 2.0 kg more weight (p = 0.020, adjusted for baseline BMI p = 0.035), and had 36% greater final insulin dose/kg (p = 0.001). With respect to hyperglycemia type, there was no difference between NPH and glargine in their effects on HbA1c. When starting bedtime insulin in type 2 diabetes patients, those with fasting type hyperglycemia are prone to greater weight gain. Hyperglycemia type does not help in identifying patients who would benefit specially from either NPH insulin or insulin glargine.
Ruiz-Herrera, Xarubet; de Los Ríos, Ericka A; Díaz, Juan M; Lerma-Alvarado, Ricardo M; Martínez de la Escalera, Lucía; López-Barrera, Fernando; Lemini, María; Arnold, Edith; Martínez de la Escalera, Gonzalo; Clapp, Carmen; Macotela, Yazmín
Excessive accumulation of body fat triggers insulin resistance and features of the metabolic syndrome. Recently, evidence has accumulated that obesity, type 2 diabetes, and metabolic syndrome are associated with reduced levels of serum prolactin (PRL) in humans and rodents, raising the question of whether low PRL levels contribute to metabolic dysfunction. Here, we have addressed this question by investigating the role of PRL in insulin sensitivity and adipose tissue fitness in obese rodents and humans. In diet-induced obese rats, treatment with PRL delivered via osmotic mini-pumps, improved insulin sensitivity, prevented adipocyte hypertrophy, and reduced inflammatory cytokine expression in visceral fat. PRL also induced increased expression of Pparg and Xbp1s in visceral adipose tissue and elevated circulating adiponectin levels. Conversely, PRL receptor null mice challenged with a high-fat diet developed greater insulin resistance, glucose intolerance, and increased adipocyte hypertrophy compared with wild-type mice. In humans, serum PRL values correlated positively with systemic adiponectin levels and were reduced in insulin-resistant patients. Furthermore, PRL circulating levels and PRL produced by adipose tissue correlated directly with the expression of PPARG, ADIPOQ, and GLUT4 in human visceral and sc adipose tissue. Thus, PRL, acting through its cognate receptors, promotes healthy adipose tissue function and systemic insulin sensitivity. Increasing the levels of PRL in the circulation may have therapeutic potential against obesity-induced metabolic diseases. Copyright © 2017 by the Endocrine Society.
Patrick E. MacDonald
Full Text Available The secretion of insulin by pancreatic islet β-cells plays a pivotal role in glucose homeostasis and diabetes. Recent work suggests an important role for SUMOylation in the control of insulin secretion from β-cells. In this paper we discuss mechanisms whereby (deSUMOylation may control insulin release by modulating β-cell function at one or more key points; and particularly through the acute and reversible regulation of the exocytotic machinery. Furthermore, we postulate that the SUMO-specific protease SENP1 is an important mediator of insulin exocytosis in response to NADPH, a metabolic secretory signal and major determinant of β-cell redox state. Dialysis of mouse β-cells with NADPH efficiently amplifies β-cell exocytosis even when extracellular glucose is low; an effect that is lost upon knockdown of SENP1. Conversely, over-expression of SENP1 itself augments β-cell exocytosis in a redox-dependent manner. Taken together, we suggest that (deSUMOylation represents an important mechanism that acutely regulates insulin secretion and that SENP1 can act as an amplifier of insulin exocytosis.
Kouritas, V K; Hatzoglou, C; Ioannou, M; Gourgoulianis, K I; Molyvdas, P A
Insulin promotes ion transportation across epithelia, mainly kidneys, leading to water and electrolyte abnormalities, possibly causing 'insulin oedema syndrome', which rarely presents as pleural effusion. Direct stimulation of sheep pleura by insulin and the possible electrophysiology mechanisms involved were investigated. Sheep visceral and parietal pleural specimens were mounted between Ussing chambers. Insulin solutions (10 (-9) to 10 (-5) M), L-NAME, Nitroprussid sodium, amiloride and ouabain were used. Trans-mesothelial Resistance was determined. Immunohistochemistry for presence of Insulin Receptors was performed. Insulin increased Trans-mesothelial Resistance within 1st minute when added mesothelially of visceral (p=0.008) and parietal pleura (p=0.046) for concentrations higher than 10 (-7) M. L-NAME or Nitroprussid sodium didn't but amiloride and ouabain inhibited insulin's effect. Immunohistochemistry revealed the presence of Insulin Receptors. Insulin changes the permeability of sheep pleura by altering its electrophysiology and may interfere in pleural effusion formation. Involvement of Insulin Receptors may be suggested.
Schmidt, Vanessa; Schulz, Nadja; Yan, Xin; Schürmann, Annette; Kempa, Stefan; Kern, Matthias; Blüher, Matthias; Poy, Matthew N; Olivecrona, Gunilla; Willnow, Thomas E
In humans, genetic variation of sortilin-related receptor, L(DLR class) A repeats containing (SORL1), which encodes the intracellular sorting receptor SORLA, is a major genetic risk factor for familial and sporadic forms of Alzheimer's disease. Recent GWAS analysis has also associated SORL1 with obesity in humans and in mouse models, suggesting that this receptor may play a role in regulating metabolism. Here, using mouse models with genetic loss or tissue-specific overexpression of SORLA as well as data from obese human subjects, we observed a gene-dosage effect that links SORLA expression to obesity and glucose tolerance. Overexpression of human SORLA in murine adipose tissue blocked hydrolysis of triacylglycerides and caused excessive adiposity. In contrast, Sorl1 gene inactivation in mice accelerated breakdown of triacylglycerides in adipocytes and protected animals from diet-induced obesity. We then identified the underlying molecular mechanism whereby SORLA promotes insulin-induced suppression of lipolysis in adipocytes. Specifically, we determined that SORLA acts as a sorting factor for the insulin receptor (IR) that redirects internalized receptor molecules from endosomes to the plasma membrane, thereby enhancing IR surface expression and strengthening insulin signal reception in target cells. Our findings provide a molecular mechanism for the association of SORL1 with human obesity and confirm a genetic link between neurodegeneration and metabolism that converges on the receptor SORLA.
T. J. Whitmore
Full Text Available Despite the important role that insulin plays in the human body, very little is known about its presence in human milk. Levels rapidly decrease during the first few days of lactation and then, unlike other serum proteins of similar size, achieve comparable levels to those in serum. Despite this, current guides for medical treatment suggest that insulin does not pass into milk, raising the question of where the insulin in milk originates. Five mothers without diabetes, 4 mothers with type 1, and 5 mothers with type 2 diabetes collected milk samples over a 24-hour period. Samples were analysed for total and endogenous insulin content and for c-peptide content. All of the insulin present in the milk of type 1 mothers was artificial, and c-peptide levels were 100x lower than in serum. This demonstrates that insulin is transported into human milk at comparable concentration to serum, suggesting an active transport mechanism. The role of insulin in milk is yet to be determined; however, there are a number of potential implications for the infant of the presence of artificial insulins in milk.
Full Text Available The type 2 diabetes has increased rapidly in recent years throughout the world. The insulin signal transduction mechanism gets disrupted sometimes and it's known as insulin-resistance. It is one of the primary causes associated with type-2 diabetes. The signaling mechanisms involved several proteins that include 7 major functional proteins such as INS, INSR, IRS1, IRS2, PIK3CA, Akt2, and GLUT4. Using these 7 principal proteins, multiple sequences alignment has been created. The scores between sequences also have been developed. We have constructed a phylogenetic tree and modified it with node and distance. Besides, we have generated sequence logos and ultimately developed the protein-protein interaction network. The small insulin signal transduction protein arrangement shows complex network between the functional proteins.
Chai, Weidong; Zhang, Xingxing; Barrett, Eugene J.; Liu, Zhenqi
Glucagon-like peptide 1 (GLP-1) acutely recruits muscle microvasculature, increases muscle delivery of insulin, and enhances muscle use of glucose, independent of its effect on insulin secretion. To examine whether GLP-1 modulates muscle microvascular and metabolic insulin responses in the setting of insulin resistance, we assessed muscle microvascular blood volume (MBV), flow velocity, and blood flow in control insulin-sensitive rats and rats made insulin-resistant acutely (systemic lipid in...
Miras, A D; Herring, R; Vusirikala, A; Shojaee-Moradi, F; Jackson, N C; Chandaria, S; Jackson, S N; Goldstone, A P; Hakim, N; Patel, A G; Umpleby, A M; Le Roux, C W
Unlike gastric banding or sleeve gastrectomy procedures, intestinal bypass procedures, Roux-en-Y gastric bypass in particular, lead to rapid improvements in glycaemia early after surgery. The bypass of the proximal small bowel may have weight loss and even caloric restriction-independent glucose-lowering properties on hepatic insulin sensitivity. In this first human mechanistic study, we examined this hypothesis by investigating the early effects of the duodeno-jejunal bypass liner (DJBL; GI Dynamics, USA) on the hepatic insulin sensitivity by using the gold standard euglycaemic hyperinsulinaemic clamp methodology. Seven patients with obesity underwent measurement of hepatic insulin sensitivity at baseline, 1 week after a low-calorie liquid diet and after a further 1 week following insertion of the DJBL whilst on the same diet. Duodeno-jejunal bypass liner did not improve the insulin sensitivity of hepatic glucose production beyond the improvements achieved with caloric restriction. Caloric restriction may be the predominant driver of early increases in hepatic insulin sensitivity after the endoscopic bypass of the proximal small bowel. The same mechanism may be at play after Roux-en-Y gastric bypass and explain, at least in part, the rapid improvements in glycaemia.
Zhao, Lina; Fu, Zhuo; Wu, Jing; Aylor, Kevin W; Barrett, Eugene J; Cao, Wenhong; Liu, Zhenqi
Adiponectin is an adipokine with anti-inflammatory and anti-diabetic properties. Hypoadiponectinaemia is closely associated with endothelial dysfunction and insulin resistance in obesity and diabetes. Insulin resistance is present in muscle microvasculature and this may contribute to decreased insulin delivery to, and action in, muscle. In this study we examined whether adiponectin ameliorates metabolic insulin resistance by affecting muscle microvascular recruitment. We demonstrated that a high-fat diet induces vascular adiponectin and insulin resistance but globular adiponectin administration can restore vascular insulin responses and improve insulin's metabolic action via an AMPK- and nitric oxide-dependent mechanism. This suggests that globular adiponectin might have a therapeutic potential for improving insulin resistance and preventing cardiovascular complications in patients with diabetes via modulation of microvascular insulin responses. Hypoadiponectinaemia is closely associated with endothelial dysfunction and insulin resistance, and microvasculature plays a critical role in the regulation of insulin action in muscle. Here we tested whether adiponectin replenishment could improve metabolic insulin sensitivity in male rats fed a high-fat diet (HFD) via the modulation of microvascular insulin responses. Male Sprague-Dawley rats were fed either a HFD or low-fat diet (LFD) for 4 weeks. Small resistance artery myograph changes in tension, muscle microvascular recruitment and metabolic response to insulin were determined. Compared with rats fed a LFD, HFD feeding abolished the vasodilatory actions of globular adiponectin (gAd) and insulin on pre-constricted distal saphenous arteries. Pretreatment with gAd improved insulin responses in arterioles isolated from HFD rats, which was blocked by AMP-activated protein kinase (AMPK) inhibition. Similarly, HFD abolished microvascular responses to either gAd or insulin and decreased insulin-stimulated glucose disposal by
Peschke, Elmar; Bähr, Ina; Mühlbauer, Eckhard
The pineal hormone melatonin exerts its influence in the periphery through activation of two specific trans-membrane receptors: MT1 and MT2. Both isoforms are expressed in the islet of Langerhans and are involved in the modulation of insulin secretion from β-cells and in glucagon secretion from α-cells. De-synchrony of receptor signaling may lead to the development of type 2 diabetes. This notion has recently been supported by genome-wide association studies identifying particularly the MT2 as a risk factor for this rapidly spreading metabolic disturbance. Since melatonin is secreted in a clearly diurnal fashion, it is safe to assume that it also has a diurnal impact on the blood-glucose-regulating function of the islet. This factor has hitherto been underestimated; the disruption of diurnal signaling within the islet may be one of the most important mechanisms leading to metabolic disturbances. The study of melatonin–insulin interactions in diabetic rat models has revealed an inverse relationship: an increase in melatonin levels leads to a down-regulation of insulin secretion and vice versa. Elucidation of the possible inverse interrelationship in man may open new avenues in the therapy of diabetes. PMID:23535335
Farouqi, Ahmed; Chadli, Asmae
The A1chieve, a multicentric (28 countries), 24-week, non-interventional study evaluated the safety and effectiveness of insulin detemir, biphasic insulin aspart and insulin aspart in people with T2DM (n = 66,726) in routine clinical care across four continents. Data was collected at baseline, at 12 weeks and at 24 weeks. This short communication presents the results for patients enrolled from Casablanca, Morocco. A total of 495 patients were enrolled in the study. Four different insulin analogue regimens were used in the study. Study patients had started on or were switched to biphasic insulin aspart (n = 231), insulin detemir (n = 151), insulin aspart (n = 19), basal insulin plus insulin aspart (n = 53) and other insulin combinations (n = 41). At baseline glycaemic control was poor for both insulin naïve (mean HbA1c: 10.2%) and insulin user (mean HbA1c: 9.4%) groups. After 24 weeks of treatment, both groups showed improvement in HbA1c (insulin naïve: -2.3%, insulin users: -1.8%). Major hypoglycaemia was observed in the insulin naïve group after 24 weeks. SADRs were reported in 1.2% of insulin naïve and 2.1% of insulin user groups. Starting or switching to insulin analogues was associated with improvement in glycaemic control with a low rate of hypoglycaemia.
Full Text Available Background: The A 1 chieve, a multicentric (28 countries, 24-week, non-interventional study evaluated the safety and effectiveness of insulin detemir, biphasic insulin aspart and insulin aspart in people with T2DM (n = 66,726 in routine clinical care across four continents. Materials and Methods: Data was collected at baseline, at 12 weeks and at 24 weeks. This short communication presents the results for patients enrolled from Casablanca, Morocco. Results: A total of 495 patients were enrolled in the study. Four different insulin analogue regimens were used in the study. Study patients had started on or were switched to biphasic insulin aspart (n = 231, insulin detemir (n = 151, insulin aspart (n = 19, basal insulin plus insulin aspart (n = 53 and other insulin combinations (n = 41. At baseline glycaemic control was poor for both insulin naïve (mean HbA 1 c: 10.2% and insulin user (mean HbA 1 c: 9.4% groups. After 24 weeks of treatment, both groups showed improvement in HbA 1 c (insulin naïve: −2.3%, insulin users: −1.8%. Major hypoglycaemia was observed in the insulin naïve group after 24 weeks. SADRs were reported in 1.2% of insulin naïve and 2.1% of insulin user groups. Conclusion: Starting or switching to insulin analogues was associated with improvement in glycaemic control with a low rate of hypoglycaemia.
Højlund, Kurt; Wojtaszewski, Jørgen F.P.; Birk, J.
AIMS/HYPOTHESIS: Recently we reported the coexistence of postprandial hypoglycaemia and moderate insulin resistance in heterozygous carriers of the Arg1174Gln mutation in the insulin receptor gene (INSR). Controlled studies of in vivo insulin signalling in humans with mutant INSR are unavailable...... in vivo insulin signalling in muscle in these carriers of a mutant INSR, probably by increasing insulin action on the non-mutated insulin receptors......., and therefore the cellular mechanisms underlying insulin resistance in Arg1174Gln carriers remain to be clarified. SUBJECTS, MATERIALS AND METHODS: We studied glucose metabolism and insulin signalling in skeletal muscle from six Arg1174Gln carriers and matched control subjects during a euglycaemic...
Samadder, Asmita; Das, Jayeeta; Das, Sreemanti; De, Arnab; Saha, Santu Kumar; Bhattacharyya, Soumya Sundar; Khuda-Bukhsh, Anisur Rahman, E-mail: firstname.lastname@example.org
attenuates arsenic-induced diabetes in mice. ► Encapsulated insulin acts effectively at nearly 10 fold lesser dose than insulin. ► Injection route is more effective than oral administration route. ► Nano-insulin can cross blood–brain barrier with added physiological implications. ► Nano-insulin acts mainly through regulation of mitochondrial signaling cascade.
Juan M Murillo-Maldonado
Full Text Available Coordination between growth and patterning/differentiation is critical if appropriate final organ structure and size is to be achieved. Understanding how these two processes are regulated is therefore a fundamental and as yet incompletely answered question. Here we show through genetic analysis that the phospholipase C-γ (PLC-γ encoded by small wing (sl acts as such a link between growth and patterning/differentiation by modulating some MAPK outputs once activated by the insulin pathway; particularly, sl promotes growth and suppresses ectopic differentiation in the developing eye and wing, allowing cells to attain a normal size and differentiate properly. sl mutants have previously been shown to have a combination of both growth and patterning/differentiation phenotypes: small wings, ectopic wing veins, and extra R7 photoreceptor cells. We show here that PLC-γ activated by the insulin pathway participates broadly and positively during cell growth modulating EGF pathway activity, whereas in cell differentiation PLC-γ activated by the insulin receptor negatively regulates the EGF pathway. These roles require different SH2 domains of PLC-γ, and act via classic PLC-γ signaling and EGF ligand processing. By means of PLC-γ, the insulin receptor therefore modulates differentiation as well as growth. Overall, our results provide evidence that PLC-γ acts during development at a time when growth ends and differentiation begins, and is important for proper coordination of these two processes.
Mohankumar, Sureshkumar; McFarlane, James R
Curcuma longa (turmeric) has been used widely as a spice, particularly in Asian countries. It is also used in the Ayurvedic system of medicine as an antiinflammatory and antimicrobial agent and for numerous other curative properties. The aim of this study was to investigate the effects of an aqueous extract of Curcuma longa (AEC) on tissues involved in glucose homeostasis. The extract was prepared by soaking 100 g of ground turmeric in 1 L of water, which was filtered and stored at -20°C prior to use. Pancreas and muscle tissues of adult mice were cultured in DMEM with 5 or 12 mmol/L glucose and varying doses of extract. The AEC stimulated insulin secretion from mouse pancreatic tissues under both basal and hyperglycaemic conditions, although the maximum effect was only 68% of that of tolbutamide. The AEC induced stepwise stimulation of glucose uptake from abdominal muscle tissues in the presence and absence of insulin, and the combination of AEC and insulin significantly potentiated the glucose uptake into abdominal muscle tissue. However, this effect was attenuated by wortmannin, suggesting that AEC possibly acts via the insulin-mediated glucose uptake pathway. In summary, water soluble compounds of turmeric exhibit insulin releasing and mimicking actions within in vitro tissue culture conditions. Copyright © 2010 John Wiley & Sons, Ltd.
Leloup, Corinne; Tourrel-Cuzin, Cécile; Magnan, Christophe; Karaca, Melis; Castel, Julien; Carneiro, Lionel; Colombani, Anne-Laure; Ktorza, Alain; Casteilla, Louis; Pénicaud, Luc
OBJECTIVE—Insulin secretion involves complex events in which the mitochondria play a pivotal role in the generation of signals that couple glucose detection to insulin secretion. Studies on the mitochondrial generation of reactive oxygen species (ROS) generally focus on chronic nutrient exposure. Here, we investigate whether transient mitochondrial ROS production linked to glucose-induced increased respiration might act as a signal for monitoring insulin secretion. RESEARCH DESIGN AND METHODS—ROS production in response to glucose was investigated in freshly isolated rat islets. ROS effects were studied using a pharmacological approach and calcium imaging. RESULTS—Transient glucose increase from 5.5 to 16.7 mmol/l stimulated ROS generation, which was reversed by antioxidants. Insulin secretion was dose dependently blunted by antioxidants and highly correlated with ROS levels. The incapacity of β-cells to secrete insulin in response to glucose with antioxidants was associated with a decrease in ROS production and in contrast to the maintenance of high levels of ATP and NADH. Then, we investigated the mitochondrial origin of ROS (mROS) as the triggering signal. Insulin release was mimicked by the mitochondrial-complex blockers, antimycin and rotenone, that generate mROS. The adding of antioxidants to mitochondrial blockers or to glucose was used to lower mROS reversed insulin secretion. Finally, calcium imaging on perifused islets using glucose stimulation or mitochondrial blockers revealed that calcium mobilization was completely reversed using the antioxidant trolox and that it was of extracellular origin. No toxic effects were present using these pharmacological approaches. CONCLUSIONS—Altogether, these complementary results demonstrate that mROS production is a necessary stimulus for glucose-induced insulin secretion. PMID:19073765