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1.
Article in English | MEDLINE | ID: mdl-38589985

ABSTRACT

CONTEXT: With advancements in long-term survival after pancreatectomy, post-pancreatectomy diabetes has become a concern, and the risk factors are not established yet. Pancreatic islets are susceptible to ischemic damage, though there is a lack of clinical evidence regarding glycemic deterioration. OBJECTIVE: To investigate association between hypotension during pancreatectomy and development of post-pancreatectomy diabetes. DESIGN: In this retrospective, longitudinal cohort study, we enrolled patients without diabetes who underwent distal pancreatectomy or pancreaticoduodenectomy between January 2005 and December 2018, from two referral hospitals in Korea. MAIN OUTCOME MEASURES: Intraoperative hypotension [IOH] was defined as a 20% or greater reduction in systolic blood-pressure. The primary and secondary outcomes were incident diabetes and postoperative Homeostatic Model Assessment [HOMA] indices. RESULTS: We enrolled 1,129 patients (average age, 59 years; 49% men; 35% distal pancreatectomy). IOH occurred in 83% (median duration, 25 minutes; interquartile range [IQR], 5-65). During a median follow-up of 3.9 years, diabetes developed in 284 patients (25%). The cumulative incidence of diabetes was proportional to increases in the duration and depth of IOH (P < 0.001). For the median duration in an IOH when compared to a reference time of 0 minute, the hazard ratio [HR] was 1.48 (95% CI, 1.14-1.92). The effect was pronounced with distal pancreatectomy compared to pancreaticoduodenectomy. Furthermore, the duration of IOH was inversely correlated with 1-year HOMA beta-cell function (P < 0.002), but not with HOMA insulin resistance. CONCLUSIONS: These results support the hypothesis that IOH during pancreatectomy may elevate risk of diabetes by inducing beta cell insufficiency.

2.
Diabetes Metab J ; 2024 Feb 02.
Article in English | MEDLINE | ID: mdl-38310875

ABSTRACT

Background: This study assessed the efficacy and safety of triple therapy with pioglitazone 15 mg add-on versus placebo in patients with type 2 diabetes mellitus (T2DM) inadequately controlled with metformin and dapagliflozin. Methods: In this multicenter, double-blind, randomized, phase 3 study, patients with T2DM with an inadequate response to treatment with metformin (≥1,000 mg/day) plus dapagliflozin (10 mg/day) were randomized to receive additional pioglitazone 15 mg/day (n=125) or placebo (n=125) for 24 weeks. The primary endpoint was the change in glycosylated hemoglobin (HbA1c) levels from baseline to week 24 (ClinicalTrials.gov identifier: NCT05101135). Results: At week 24, the adjusted mean change from baseline in HbA1c level compared with placebo was significantly greater with pioglitazone treatment (-0.47%; 95% confidence interval, -0.61 to -0.33; P<0.0001). A greater proportion of patients achieved HbA1c <7% or <6.5% at week 24 with pioglitazone compared to placebo as add-on to 10 mg dapagliflozin and metformin (56.8% vs. 28% for HbA1c <7%, and 23.2% vs. 9.6% for HbA1c <6.5%; P<0.0001 for all). The addition of pioglitazone also significantly improved triglyceride, highdensity lipoprotein cholesterol levels, and homeostatic model assessment of insulin resistance levels, while placebo did not. The incidence of treatment-emergent adverse events was similar between the groups, and the incidence of fluid retention-related side effects by pioglitazone was low (1.5%). Conclusion: Triple therapy with the addition of 15 mg/day of pioglitazone to dapagliflozin plus metformin was well tolerated and produced significant improvements in HbA1c in patients with T2DM inadequately controlled with dapagliflozin plus metformin.

3.
Diabetes Metab J ; 48(2): 231-241, 2024 Mar.
Article in English | MEDLINE | ID: mdl-37670417

ABSTRACT

BACKGRUOUND: Administration of pancreatic endoplasmic reticulum kinase inhibitor (PERKi) improved insulin secretion and hyperglycemia in obese diabetic mice. In this study, autophagic balance was studied whether to mediate it. METHODS: Human islets were isolated from living patients without diabetes. PERKi GSK2606414 effects were evaluated in the islets under glucolipotoxicity by palmitate. Islet insulin contents and secretion were measured. Autophagic flux was assessed by microtubule associated protein 1 light chain 3 (LC3) conversion, a red fluorescent protein (RFP)-green fluorescent protein (GFP)- LC3 tandem assay, and P62 levels. For mechanical analyses, autophagy was suppressed using 3-methyladenine in mouse islets. Small interfering RNA for an autophagy-related gene autophagy related 7 (Atg7) was transfected to interfere autophagy. RESULTS: PERKi administration to mice decreased diabetes-induced P62 levels in the islets. Glucolipotoxicity significantly increased PERK phosphorylation by 70% and decreased insulin contents by 50% in human islets, and addition of PERKi (40 to 80 nM) recovered both. PERKi also enhanced glucose-stimulated insulin secretion (6-fold). PERKi up-regulated LC3 conversion suppressed by glucolipotoxicity, and down-regulated P62 contents without changes in P62 transcription, indicating enhanced autophagic flux. Increased autophagosome-lysosome fusion by PERKi was visualized in mouse islets, where PERKi enhanced ATG7 bound to LC3. Suppression of Atg7 eliminated PERKi-induced insulin contents and secretion. CONCLUSION: This study provided functional changes of human islets with regard to autophagy under glucolipotoxicity, and suggested modulation of autophagy as an anti-diabetic mechanism of PERKi.


Subject(s)
Diabetes Mellitus, Experimental , Hyperglycemia , Islets of Langerhans , Humans , Mice , Animals , Insulin/metabolism , Diabetes Mellitus, Experimental/metabolism , Autophagy/genetics , Hyperglycemia/metabolism
4.
Endocrinol Metab (Seoul) ; 38(6): 782-787, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37956968

ABSTRACT

Although pancreatic endoplasmic reticulum kinase (PERK) is indispensable to beta cells, low-dose PERK inhibitor improved glucose- stimulated insulin secretion (GSIS) and hyperglycemia in diabetic mice. Current study examined if partial deletion of Perk (Perk+/-) recapitulated the effects of PERK inhibitor, on the contrary to the complete deletion. Perk+/- mice and wild-type controls were fed with a high-fat diet (HFD) for 23 weeks. Glucose tolerance was evaluated along with serum insulin levels and islet morphology. Perk+/- mice on normal chow were comparable to wild-type mice in various metabolic features. HFD-induced obesity was not influenced by Perk reduction; however, HFD-induced glucose intolerance was significantly improved since 15-week HFD. HFD-induced compromises in GSIS were relieved by Perk reduction, accompanied by reductions in phosphorylated PERK and activating transcription factor 4 (ATF4) in the islets. Meanwhile, HFD-induced islet expansion was not significantly affected. In summary, partial deletion of Perk improved glucose tolerance and GSIS impaired by diet-induced obesity, without changes in body weights or islet mass.


Subject(s)
Diabetes Mellitus, Experimental , Glucose Intolerance , Islets of Langerhans , Animals , Mice , Diabetes Mellitus, Experimental/metabolism , Diet, High-Fat , Glucose , Insulin/metabolism , Islets of Langerhans/metabolism , Obesity/metabolism
5.
Stem Cells Transl Med ; 12(7): 485-495, 2023 Jul 14.
Article in English | MEDLINE | ID: mdl-37350544

ABSTRACT

Bone marrow-derived stem cells are self-renewing and multipotent adult stem cells that differentiate into several types of cells. Here, we investigated a unique combination of 4 differentiation-inducing factors (DIFs), including putrescine (Put), glucosamine (GlcN), nicotinamide, and BP-1-102, to develop a differentiation method for inducing mature insulin-producing cells (IPCs) and apply this method to bone marrow mononucleated cells (BMNCs) isolated from mice. BMNCs, primed with the 4 soluble DIFs, were differentiated into functional IPCs. BMNCs cultured under the defined conditions synergistically expressed multiple genes, including those for PDX1, NKX6.1, MAFA, NEUROG3, GLUT2, and insulin, related to pancreatic beta cell development and function. They produced insulin/C-peptide and PDX1, as assessed using immunofluorescence and flow cytometry. The induced cells secreted insulin in a glucose-responsive manner, similar to normal pancreatic beta cells. Grafting BMNC-derived IPCs under kidney capsules of mice with streptozotocin (STZ)-induced diabetes alleviated hyperglycemia by lowering blood glucose levels, enhancing glucose tolerance, and improving glucose-stimulated insulin secretion. Insulin- and PDX1-expressing cells were observed in the IPC-bearing graft sections of nephrectomized mice. Therefore, this study provides a simple protocol for BMNC differentiation, which can be a novel approach for cell-based therapy in diabetes mellitus.


Subject(s)
Diabetes Mellitus, Experimental , Insulin-Secreting Cells , Mesenchymal Stem Cells , Mice , Animals , Bone Marrow , Cell Differentiation , Glucose , Diabetes Mellitus, Experimental/therapy , Insulin , Bone Marrow Cells
6.
Diabetes Metab J ; 46(4): 533-542, 2022 07.
Article in English | MEDLINE | ID: mdl-35929171

ABSTRACT

Pancreatic beta cell homeostasis is crucial for the synthesis and secretion of insulin; disruption of homeostasis causes diabetes, and is a treatment target. Adaptation to endoplasmic reticulum (ER) stress through the unfolded protein response (UPR) and adequate regulation of autophagy, which are closely linked, play essential roles in this homeostasis. In diabetes, the UPR and autophagy are dysregulated, which leads to beta cell failure and death. Various studies have explored methods to preserve pancreatic beta cell function and mass by relieving ER stress and regulating autophagic activity. To promote clinical translation of these research results to potential therapeutics for diabetes, we summarize the current knowledge on ER stress and autophagy in human insulin-secreting cells.


Subject(s)
Diabetes Mellitus , Insulin-Secreting Cells , Autophagy , Diabetes Mellitus/metabolism , Endoplasmic Reticulum/metabolism , Endoplasmic Reticulum Stress , Humans , Insulin-Secreting Cells/metabolism
7.
Diabetes Metab J ; 46(3): 439-450, 2022 05.
Article in English | MEDLINE | ID: mdl-34666425

ABSTRACT

BACKGROUND: Prevailing insulin regimens for glycemic control in hospitalized patients have changed over time. We aimed to determine whether the current basal-bolus insulin (BBI) regimen is superior to the previous insulin regimen, mainly comprising split-mixed insulin therapy. METHODS: This was a single tertiary center, retrospective observational study that included non-critically ill patients with type 2 diabetes mellitus who were treated with split-mixed insulin regimens from 2004 to 2007 (period 1) and with BBI from 2008 to 2018 (period 2). Patients from each period were analyzed after propensity score matching. The mean difference in glucose levels and the achievement of fasting and preprandial glycemic targets by day 6 of admission were assessed. The total daily insulin dose, incidence of hypoglycemia, and length of hospital stay were also evaluated. RESULTS: Among 244 patients from each period, both fasting glucose (estimated mean±standard error, 147.4±3.1 mg/dL vs. 129.4±3.2 mg/dL, P<0.001, day 6) and preprandial glucose (177.7±2.8 mg/dL vs. 152.8±2.8 mg/dL, P<0.001, day 6) were lower in period 2 than in period 1. By day 6 of hospital admission, 42.6% and 67.2% of patients achieved a preprandial glycemic target of <140 mg/dL in periods 1 and 2, respectively (relative risk, 2.00; 95% confidence interval, 1.54 to 2.59), without an increased incidence of hypoglycemia. Length of stay was shorter in period 2 (10.23±0.26 days vs. 8.70±0.26 days, P<0.001). CONCLUSION: BBI improved glycemic control in a more efficacious manner than a split-mixed insulin regimen without increasing the risk of hypoglycemia in a hospital setting.


Subject(s)
Diabetes Mellitus, Type 2 , Hypoglycemia , Biphasic Insulins/therapeutic use , Blood Glucose , Diabetes Mellitus, Type 2/drug therapy , Diabetes Mellitus, Type 2/epidemiology , Humans , Hypoglycemia/chemically induced , Hypoglycemia/epidemiology , Hypoglycemic Agents/therapeutic use , Insulin/therapeutic use , Tertiary Care Centers
8.
J Diabetes Investig ; 13(1): 85-93, 2022 Jan.
Article in English | MEDLINE | ID: mdl-34291584

ABSTRACT

AIMS/INTRODUCTION: The benefits of once-daily insulin degludec/aspart (IDegAsp) compared with basal insulin in type 2 diabetes patients have not been established. MATERIALS AND METHODS: This was a retrospective observational study. From a basal insulin cohort from three referral hospitals, patients were enrolled who initiated once-daily IDegAsp. A control group maintaining basal insulin was selected by propensity score matching. Glycated hemoglobin (HbA1c) changes over a period of 6 months and associated clinical factors were evaluated. RESULTS: The IDegAsp group and the control group comprised of 87 patients, respectively. Baseline HbA1c was comparable between the two groups (8.7 ± 0.9 vs 8.6 ± 0.9%, mean and standard deviation). After 6 months with matched insulin doses, HbA1c in the IDegAsp group was lower than that in the control group (8.1 ± 1.0 vs 8.4 ± 1.1%, P = 0.029). Among baseline variables, fasting plasma glucose (FPG) and fasting C-peptide in the IDegAsp were lower than that in the control (FPG 124.2 ± 38.4 vs 148.0 ± 50.6 mg/dL, P < 0.001). Considering that the lower FPG despite the comparable HbA1c could be related with the efficacy of IDegAsp, subgroup analysis was carried out according to a ratio of FPG-to-estimated average glucose, which is calculated from HbA1c. When compared with each control group, the superiority of IDegAsp in the reduction of HbA1c was significant only in the patients with a lower FPG-to-estimated average glucose ratio (0.49 ± 0.09), but not in those with a higher FPG-to-estimated average glucose ratio (0.79 ± 0.20). CONCLUSIONS: We observed that IDegAsp was more effective than basal insulin in patients with an FPG lower than predicted by HbA1c, which might be related with insulin deficiency and postprandial hyperglycemia in patients on basal insulin therapy.


Subject(s)
Blood Glucose/drug effects , Diabetes Mellitus, Type 2/drug therapy , Hypoglycemic Agents/therapeutic use , Insulin, Long-Acting/therapeutic use , Aged , C-Peptide/blood , Diabetes Mellitus, Type 2/blood , Drug Combinations , Fasting/blood , Female , Glycated Hemoglobin/drug effects , Humans , Hyperglycemia/chemically induced , Male , Middle Aged , Retrospective Studies
9.
Diabetes Metab J ; 46(1): 71-80, 2022 01.
Article in English | MEDLINE | ID: mdl-34130445

ABSTRACT

BACKGROUND: To compare the efficacy and safety of two insulin self-titration algorithms, Implementing New Strategies with Insulin Glargine for Hyperglycemia Treatment (INSIGHT) and EDITION, for insulin glargine 300 units/mL (Gla-300) in Korean individuals with uncontrolled type 2 diabetes mellitus (T2DM). METHODS: In a 12-week, randomized, open-label trial, individuals with uncontrolled T2DM requiring basal insulin were randomized to either the INSIGHT (adjusted by 1 unit/day) or EDITION (adjusted by 3 units/week) algorithm to achieve a fasting self-monitoring of blood glucose (SMBG) in the range of 4.4 to 5.6 mmol/L. The primary outcome was the proportion of individuals achieving a fasting SMBG ≤5.6 mmol/L without noct urnal hypoglycemia at week 12. RESULTS: Of 129 individuals (age, 64.1±9.5 years; 66 [51.2%] women), 65 and 64 were randomized to the INSIGHT and EDITION algorithms, respectively. The primary outcome of achievement was comparable between the two groups (24.6% vs. 23.4%, P=0.876). Compared with the EDITION group, the INSIGHT group had a greater reduction in 7-point SMBG but a similar decrease in fasting plasma glucose and glycosylated hemoglobin. The increment of total daily insulin dose was significantly higher in the INSIGHT group than in the EDITION group (between-group difference: 5.8±2.7 units/day, P=0.033). However, body weight was significantly increased only in the EDITION group (0.6±2.4 kg, P=0.038). There was no difference in the occurrence of hypoglycemia between the two groups. Patient satisfaction was significantly increased in the INSIGHT group (P=0.014). CONCLUSION: The self-titration of Gla-300 using the INSIGHT algorithm was effective and safe compared with that using the EDITION algorithm in Korean individuals with uncontrolled T2DM (ClinicalTrials.gov number: NCT03406663).


Subject(s)
Diabetes Mellitus, Type 2 , Aged , Algorithms , Blood Glucose , Diabetes Mellitus, Type 2/drug therapy , Female , Humans , Hypoglycemic Agents/adverse effects , Insulin Glargine/adverse effects , Middle Aged , Republic of Korea/epidemiology
10.
Ann Transl Med ; 8(8): 561, 2020 Apr.
Article in English | MEDLINE | ID: mdl-32775362

ABSTRACT

BACKGROUND: Islet transplantation might be a logical strategy to restore insulin secretion for the treatment of diabetes, however, the scarcity of donors poses an obstacle for such a treatment. As an alternative islet source, differentiation of stem cells into insulin-producing cells (IPCs) has been tried. Many protocols have been developed to improve the efficiency of differentiation of stem cells into IPCs. In this study, we investigated whether glucosamine supplementation during differentiation of human adipose-derived stem cells (hADSCs) into IPCs can improve the insulin secretory function. METHODS: Glucosamine was added to the original differentiation medium at different stages of differentiation of hADSCs into IPCs for 12 days and insulin secretion was analyzed. RESULTS: Addition of glucosamine alone to the growth medium of hADSCs did not affect the differentiation of hADSCs to IPCs. Supplementation of the differentiation medium with glucosamine at a later stage (protocol G3) proved to have the greatest effect on IPC differentiation. Basal and glucose-stimulated insulin secretion (GSIS) was significantly increased and the expression of insulin and C-peptide was increased in differentiated IPCs as compared with that in differentiated IPCs using the conventional protocol (protocol C). In addition, the expression of beta-cell specific transcription factors such as pancreatic and duodenal homeobox1 (PDX1) and neurogenin 3 (NGN3) was also increased. Furthermore, the expression of genes related to insulin secretion, including synaptotagmin 4 (Syt4), glucokinase (Gck) and glucose transporter 2 (Glut2), was also increased. CONCLUSIONS: We conclude that glucosamine supplementation potentiates the differentiation of hADSCs into IPCs.

13.
J Lipid Res ; 61(1): 33-44, 2020 01.
Article in English | MEDLINE | ID: mdl-31722970

ABSTRACT

Chronic inflammation contributes to cardiovascular disease. Increased levels of the inflammatory cytokine, TNF-α, are often present in conditions associated with cardiovascular disease risk, and TNF-α induces a number of pro-atherogenic effects in macrovascular endothelial cells, including expression of adhesion molecules and chemokines, and lipoprotein uptake and transcytosis to the subendothelial tissue. However, little is known about the roles of acyl-CoA synthetases (ACSLs), enzymes that esterify free fatty acids into their acyl-CoA derivatives, or about the effects of TNF-α on ACSLs in endothelial cells. Therefore, we investigated the effects of TNF-α on ACSLs and downstream lipids in cultured human coronary artery endothelial cells and human umbilical vein endothelial cells. We demonstrated that TNF-α induces ACSL1, ACSL3, and ACSL5, but not ACSL4, in both cell types. TNF-α also increased oleoyl-CoA levels, consistent with the increased ACSL3 expression. RNA-sequencing demonstrated that knockdown of ACSL3 had no marked effects on the TNF-α transcriptome. Instead, ACSL3 was required for TNF-α-induced lipid droplet formation in cells exposed to oleic acid. These results demonstrate that increased acyl-CoA synthesis as a result of ACSL3 induction is part of the TNF-α response in human macrovascular endothelial cells.


Subject(s)
Coenzyme A Ligases/metabolism , Endothelial Cells/drug effects , Endothelial Cells/metabolism , Lipid Droplets/drug effects , Tumor Necrosis Factor-alpha/pharmacology , Adult , Cells, Cultured , Coenzyme A Ligases/genetics , Endothelial Cells/enzymology , Female , Humans , Lipid Droplets/metabolism , Male
14.
Endocrinol Metab (Seoul) ; 34(4): 382-389, 2019 12.
Article in English | MEDLINE | ID: mdl-31884738

ABSTRACT

BACKGROUND: Conflicting results have been reported on the efficacy of insulin degludec/insulin aspart (IDegAsp) compared to basal insulin in type 2 diabetes. We investigated the effects of changing basal insulin to IDegAsp on glycemic control and sought to identify factors related to those effects. METHODS: In this retrospective study of patients from three referral hospitals, patients with type 2 diabetes using basal insulin with hemoglobin A1c (HbA1c) levels less than 11.0% were enrolled. Basal insulin was replaced with IDegAsp, and data were analyzed from 3 months before to 3 months after the replacement. RESULTS: Eighty patients were recruited (52.5% male; mean age, 67.0±9.8 years; mean duration of diabetes, 18.9±8.5 years; mean HbA1c, 8.7%±1.0%). HbA1c levels increased during 3 months of basal insulin use, but significantly decreased after changing to IDegAsp (8.28%±1.10%, P=0.0001). The reduction was significant at 6 months in 35 patients whose longer-term data were available. Patients with a measured fasting plasma glucose (m-FPG) lower than their predicted FPG (p-FPG) by regression from HbA1c showed a significant HbA1c reduction caused by the change to IDegAsp, even without a significantly increased insulin dose. However, patients whose m-FPG was higher than their p-FPG did not experience a significant HbA1c reduction, despite a significantly increased insulin dose. Furthermore, the HbA1c reduction caused by IDegAsp was significant in patients with low fasting C-peptide levels and high insulin doses. CONCLUSION: We observed a significant glucose-lowering effect by replacing basal insulin with IDegAsp, especially in patients with a lower m-FPG than p-FPG.


Subject(s)
Biomarkers/blood , Blood Glucose/analysis , Diabetes Mellitus, Type 2/drug therapy , Glycated Hemoglobin/analysis , Hypoglycemic Agents/administration & dosage , Insulin, Long-Acting/administration & dosage , Insulin/administration & dosage , Adult , Aged , Diabetes Mellitus, Type 2/blood , Diabetes Mellitus, Type 2/pathology , Drug Administration Schedule , Drug Combinations , Female , Follow-Up Studies , Humans , Male , Middle Aged , Prognosis , Retrospective Studies
15.
J Clin Endocrinol Metab ; 104(9): 4188-4198, 2019 Sep 01.
Article in English | MEDLINE | ID: mdl-30977832

ABSTRACT

PURPOSE: Monogenic diabetes is a specific type of diabetes in which precision medicine could be applied. In this study, we used targeted panel sequencing to investigate pathogenic variants in Korean patients with clinically suspected monogenic diabetes. METHODS: The eligibility criteria for inclusion were patients with nontype 1 diabetes with age at onset ≤30 years and body mass index (BMI) ≤30 kg/m2. Among the 2090 patients with nontype 1 diabetes, 109 had suspected monogenic diabetes and underwent genetic testing. We analyzed 30 monogenic diabetes genes using targeted panel sequencing. The pathogenicity of the genetic variants was evaluated according to the American College of Medical Genetics and Genomics and Association for Molecular Pathology guidelines. RESULTS: Among the 109 patients with suspected monogenic diabetes, 23 patients (21.1%) harbored pathogenic/likely pathogenic variants. A total of 14 pathogenic/likely pathogenic variants of common maturity-onset diabetes of the young (MODY) genes were identified in GCK, HNF1A, HNF4A, and HNF1B. Other pathogenic/likely pathogenic variants were identified in WFS1, INS, ABCC8, and FOXP3. The mitochondrial DNA 3243A>G variant was identified in five participants. Patients with pathogenic/likely pathogenic variants had a significantly higher MODY probability, a lower BMI, and a lower C-peptide level than those without pathogenic/likely pathogenic variants (P = 0.007, P = 0.001, and P = 0.012, respectively). CONCLUSIONS: Using targeted panel sequencing followed by pathogenicity evaluation, we were able to make molecular genetic diagnoses for 23 patients (21.1%) with suspected monogenic diabetes. Lower BMI, higher MODY probability, and lower C-peptide level were characteristics of these participants.

16.
Sci Rep ; 9(1): 5343, 2019 03 29.
Article in English | MEDLINE | ID: mdl-30926860

ABSTRACT

Transplantation of stem cell-derived insulin producing cells (IPCs) has been proposed as an alternative to islet transplantation for the treatment of diabetes mellitus. However, current IPC differentiation protocols are focused on generating functional cells from the pluripotent stem cells and tend to rely on multistep, long-term exposure to various exogenous factors. In this study, we addressed the observation that under stress, pancreatic ß-cells release essential components that direct the differentiation of the bone marrow nucleated cells (BMNCs) into IPCs. Without any supplementation with known differentiation-inducing factors, IPCs can be generated from BMNCs by in vitro priming for 6 days with conditioned media (CM) from the ß-cells. In vitro primed BMNCs expressed the ß-cell-specific transcription factors, as well as insulin, and improved hyperglycemia and glucose intolerance after transplantation into the streptozotocin-induced diabetic mice. Furthermore, we have found that components of the CM which trigger the differentiation were enclosed by or integrated into micro particles (MPs), rather than being secreted as soluble factors. Identification of these differentiation-directing factors might enable us to develop novel technologies required for the production of clinically applicable IPCs.


Subject(s)
Bone Marrow Cells/cytology , Cell Differentiation , Insulin-Secreting Cells/cytology , Insulin-Secreting Cells/metabolism , Animals , Biomarkers , Blood Glucose , Cell- and Tissue-Based Therapy , Cells, Cultured , Diabetes Mellitus, Experimental , Fluorescent Antibody Technique , Genes, Reporter , Humans , Insulin/biosynthesis , Insulin-Secreting Cells/transplantation , Mesenchymal Stem Cells/cytology , Mice
17.
Metabolism ; 97: 87-91, 2019 08.
Article in English | MEDLINE | ID: mdl-30615948

ABSTRACT

BACKGROUND: We have reported that partial PERK attenuation using PERK inhibitors (PI) enhanced glucose-stimulated insulin secretion (GSIS) from pancreatic islets and mice through induction of ER chaperone BIP. Therefore, we investigated if PI would have the same effects in a diabetic condition as well. METHODS: GSK2606414 was treated to mouse islets under 20-mM glucose and 0.5-mM palmitate to examine GSIS. To generate a mouse model of type 2 diabetes mellitus (DM), male C57BL/6J mice were fed with high-fat diet and injected with streptozotocin. Several doses (6-16 mg/kg/day) of GSK2656157 and glimepiride were administrated to the mice for 8 weeks, and metabolic phenotypes were evaluated such as body weight, blood glucose levels, insulin secretion and sensitivity, and then changes in the pancreas were measured. RESULTS: High-glucose and palmitate treatment significantly increased PERK phosphorylation in the isolated islets. Suppression of GSIS and glucose-stimulated Ca2+ transit was also observed. PI at 40 nM which decreased PERK phosphorylation by 40% significantly recovered the GSIS and cytosolic calcium. In the mice where significant weight gain and prominent hyperglycemia were induced, PI at 10 mg/kg/day significantly enhanced GSIS and reduced blood glucose levels compared to the vehicle. The effects were similar to those by 10 mg/kg/day of glimepiride. Administration of PI did not induce changes in beta cell mass or pancreatic insulin contents, however, high dose PI decreased pancreatic weight. CONCLUSION: PI at low dose significantly enhanced GSIS in vitro and in vivo under metabolic stress and improved hyperglycemia in the mice mimicking type 2 DM, suggesting a potential as a new therapeutic approach for type 2 DM.


Subject(s)
Diabetes Mellitus, Type 2/drug therapy , Diabetes Mellitus, Type 2/metabolism , Glucose/metabolism , Insulin Secretion/drug effects , Insulin/metabolism , eIF-2 Kinase/antagonists & inhibitors , Adenine/analogs & derivatives , Adenine/pharmacology , Animals , Disease Models, Animal , Hyperglycemia/drug therapy , Hyperglycemia/metabolism , Indoles/pharmacology , Insulin-Secreting Cells/drug effects , Islets of Langerhans/drug effects , Islets of Langerhans/metabolism , Male , Mice , Mice, Inbred C57BL , Palmitates/pharmacology , Sulfonylurea Compounds/pharmacology
18.
Diabetes Care ; 42(1): 3-9, 2019 01.
Article in English | MEDLINE | ID: mdl-30377185

ABSTRACT

OBJECTIVE: This study evaluated the efficacy of a smartphone-based, patient-centered diabetes care system (mDiabetes) for type 2 diabetes that contains comprehensive modules for glucose monitoring, diet, physical activity, and a clinical decision support system. RESEARCH DESIGN AND METHODS: We conducted a 24-week, multicenter, randomized controlled trial with adult patients with inadequately controlled type 2 diabetes. The patients were randomly assigned to the mDiabetes group or the paper logbook (pLogbook) group. The primary end point was the difference of the change in HbA1c from baseline between the two groups. RESULTS: HbA1c reduction from baseline was greater in the mDiabetes group (-0.40 ± 0.09%, n = 90) than in the pLogbook group (-0.06 ± 0.10%, n = 82). The difference of adjusted mean changes was 0.35% (95% CI 0.14-0.55, P = 0.001). The proportion of patients whose HbA1c fell below 7.0% (53 mmol/mol) was 41.1% for the mDiabetes group and 20.7% for the pLogbook group (odds ratio [OR] 2.01, 95% CI 1.24-3.25, P = 0.003). The percentage of patients who attained HbA1c levels below 7.0% (53 mmol/mol) without hypoglycemia was 31.1% in the mDiabetes group and 17.1% in the pLogbook group (OR 1.82, 95% CI 1.03-3.21, P = 0.024). There was no difference in the event numbers of severe hyperglycemia and hypoglycemia between the two groups. CONCLUSIONS: The implementation of the mDiabetes for patients with inadequately controlled type 2 diabetes resulted in a significant reduction in HbA1c levels, with tolerable safety profiles.


Subject(s)
Diabetes Mellitus, Type 2/therapy , Patient-Centered Care , Smartphone , Adult , Aged , Aged, 80 and over , Blood Glucose/metabolism , Blood Glucose Self-Monitoring/methods , Body Mass Index , Cholesterol/blood , Diabetes Mellitus, Type 2/blood , Female , Glycated Hemoglobin/metabolism , Humans , Hyperglycemia/blood , Hyperglycemia/therapy , Hypoglycemia/blood , Hypoglycemia/therapy , Hypoglycemic Agents/therapeutic use , Insulin/blood , Insulin/therapeutic use , Male , Middle Aged , Pilot Projects , Triglycerides/blood , Young Adult
19.
J Endocrinol ; 239(3): 277-287, 2018 12 01.
Article in English | MEDLINE | ID: mdl-30400012

ABSTRACT

Rodent stem cells demonstrated regenerative effects in diabetic neuropathy via improvement in nerve perfusion. As a pre-clinical step, we explored if human mobilized mononuclear cells (hMNC) would have the same effects in rats. hMNC were injected into Rt. hind-limb muscles of streptozotocin-induced diabetic nude rats, and the grafts were monitored using with MRI. After 4 weeks, the effects were compared with those in the vehicle-injected Lt. hind limbs. Nerve conduction, muscle perfusion and gene expression of sciatic nerves were assessed. Induction of diabetes decreased nerve function and expression of Mpz and Met in the sciatic nerves, which are related with myelination. hMNC injection significantly improved the amplitude of compound muscle action potentials along with muscle perfusion and sciatic nerve Mpz expression. On MRI, hypointense signals were observed for 4 weeks at the graft site, but their correlation with the presence of hMNC was detectable for only 1 week. To evaluate paracrine effects of hMNC, IMS32 cells were tested with hepatocyte growth factor (HGF), which had been reported as a myelination-related factor from stem cells. We could observe that HGF enhanced Mpz expression in the IMS32 cells. Because hMNC secreted HGF, IMS32 cells were co-cultured with hMNC, and the expression of Mpz increased along with morphologic maturation. The hMNC-induced Mpz expression was abrogated by treatment of anti-HGF. These results suggest that hMNC could improve diabetic neuropathy, possibly through enhancement of myelination as well as perfusion. According to in vitro studies, HGF was involved in the hMNC-induced myelination activity, at least in part.


Subject(s)
Diabetic Nephropathies/therapy , Leukocytes, Mononuclear/transplantation , Action Potentials , Adult , Animals , Blood Glucose , Cell Line , Coculture Techniques , Humans , Magnetic Resonance Imaging , Male , Mice , Myelin P0 Protein/metabolism , Rats, Nude , Rats, Sprague-Dawley , Sciatic Nerve/metabolism
20.
Diabetes ; 67(12): 2601-2614, 2018 12.
Article in English | MEDLINE | ID: mdl-30257975

ABSTRACT

Glucagon-like peptide 1 (GLP-1) can increase pancreatic ß-cells, and α-cells could be a source for new ß-cell generation. We investigated whether GLP-1 increases ß-cells through α-cell transdifferentiation. New ß-cells originating from non-ß-cells were significantly increased in recombinant adenovirus expressing GLP-1 (rAd-GLP-1)-treated RIP-CreER;R26-YFP mice. Proliferating α-cells were increased in islets of rAd-GLP-1-treated mice and αTC1 clone 9 (αTC1-9) cells treated with exendin-4, a GLP-1 receptor agonist. Insulin+glucagon+ cells were significantly increased by rAd-GLP-1 or exendin-4 treatment in vivo and in vitro. Lineage tracing to label the glucagon-producing α-cells showed a higher proportion of regenerated ß-cells from α-cells in rAd-GLP-1-treated Glucagon-rtTA;Tet-O-Cre;R26-YFP mice than rAd producing ß-galactosidase-treated mice. In addition, exendin-4 increased the expression and secretion of fibroblast growth factor 21 (FGF21) in αTC1-9 cells and ß-cell-ablated islets. FGF21 treatment of ß-cell-ablated islets increased the expression of pancreatic and duodenal homeobox-1 and neurogenin-3 and significantly increased insulin+glucagon+ cells. Generation of insulin+glucagon+ cells by exendin-4 was significantly reduced in islets transfected with FGF21 small interfering RNA or islets of FGF21 knockout mice. Generation of insulin+ cells by rAd-GLP-1 treatment was significantly reduced in FGF21 knockout mice compared with wild-type mice. We suggest that GLP-1 has an important role in α-cell transdifferentiation to generate new ß-cells, which might be mediated, in part, by FGF21 induction.


Subject(s)
Cell Transdifferentiation/drug effects , Exenatide/pharmacology , Glucagon-Like Peptide 1/metabolism , Glucagon-Secreting Cells/cytology , Insulin-Secreting Cells/cytology , Islets of Langerhans/drug effects , Animals , Cell Proliferation/drug effects , Glucagon-Like Peptide 1/genetics , Glucagon-Secreting Cells/drug effects , Glucagon-Secreting Cells/metabolism , Insulin-Secreting Cells/drug effects , Insulin-Secreting Cells/metabolism , Islets of Langerhans/metabolism , Mice , Regeneration/drug effects
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