Short-term recovery of insulin secretion in response to a meal is associated with future glycemic control in type 2 diabetes patients

AIMS/INTRODUCTION

Endogenous insulin secretion could be recovered by improving hyperglycemia in patients with type 2 diabetes. This study aimed to investigate the association between short-term recovery of insulin secretion during hospitalization and clinical background or future glycemic control in patients with type 2 diabetes.

MATERIALS AND METHODS

A total of 127 patients with type 2 diabetes were included. The recovery of endogenous insulin secretion was determined using the following indices: index A: fasting C-peptide index (CPI) at discharge - fasting CPI on admission; index B: postprandial CPI at discharge - postprandial CPI on admission; and index C: Δ C-peptide immunoreactivity (CPR) (postprandial CPR - fasting CPR) at discharge - ΔCPR on admission. We examined the associations of each index with clinical background and future glycemic control measured by glycosylated hemoglobin and continuous glucose monitoring.

RESULTS

Using index A and B, the age was significantly younger, whereas BMI and visceral fat area were significantly higher in the high-recovery group than in the low-recovery group. Changes in glycosylated hemoglobin levels were significantly greater at 6 and 12 months in the high-recovery group in the analysis of index C. The receiver operating characteristic curve analysis identified the index B and index C as indicators to predict glycosylated hemoglobin <7.0% at 6 months after discharge. Furthermore, index C was positively correlated with the time in the target glucose range, and inversely correlated with the standard deviation of glucose at 3 and 12 months after discharge.

CONCLUSIONS

Short-term recovery of insulin secretion in response to a meal during hospitalization, evaluated with the index-C, might predict future glycemic control.

Prediction of future insulin-deficiency in glutamic acid decarboxylase autoantibody enzyme-linked immunosorbent assay-positive patients with slowly-progressive type 1 diabetes

AIMS/INTRODUCTION

This study aimed to identify risk factors that contribute to the progression of slowly-progressive type 1 diabetes by evaluating the positive predictive value (PPV) of factors associated with the progression to an insulin-dependent state.

MATERIALS AND METHODS

We selected 60 slowly-progressive type 1 diabetes patients who tested positive for glutamic acid decarboxylase autoantibodies (GADA) at diagnosis from the Japanese Type 1 Diabetes Database Study. GADA levels in these patients were concurrently measured using both radioimmunoassay (RIA) and enzyme-linked immunosorbent assay (ELISA) techniques.

RESULTS

Compared with the non-progressor group (fasting C-peptide [F-CPR] levels maintained ≥0.6 ng/mL), the progressor group showed a younger age at diagnosis, lower body mass index (BMI), lower F-CPR levels and a higher prevalence of insulinoma-associated antigen-2 autoantibodies (IA-2A). The PPV of RIA-GADA increased from 56.3 to 70.0% in the high titer group (≥10 U/mL), and further increased to 76.9, 84.2, 81.0 and 75.0% when combined with specific thresholds for age at diagnosis <47 years, BMI <22.6 kg/m2 , F-CPR <1.41 ng/mL and IA-2A positivity, respectively. In contrast, the PPV of ELISA-GADA (71.8%) remained the same at 73.1% in the high titer group (≥180 U/mL), but increased to 81.8, 82.4 and 79.0% when evaluated in conjunction with age at diagnosis, BMI and F-CPR level, respectively.

CONCLUSIONS

Our findings show that, unlike RIA-GADA, ELISA-GADA shows no association between GADA titers and the risk of progression to an insulin-dependent state. The PPV improves when age at diagnosis, BMI and F-CPR levels are considered in combination.

New diagnostic criteria (2023) for slowly progressive type 1 diabetes (SPIDDM): Report from Committee on Type 1 Diabetes of the Japan Diabetes Society (English version)

The diagnostic criteria for slowly progressive type 1 diabetes (slowly progressive insulin-dependent diabetes mellitus; SPIDDM) have been revised by the Committee on Type 1 Diabetes of the Japan Diabetes Society. All of the following three criteria must be met for 'a definitive diagnosis of SPIDDM': (1) presence of anti-islet autoantibodies at some point in time during the disease course; (2) absence of ketosis or ketoacidosis at the diagnosis of diabetes with no requirement for insulin treatment to correct hyperglycemia immediately after diagnosis in principle; and (3) gradual decrease of insulin secretion over time, with insulin treatment required at more than 3 months after diagnosis, and the presence of severe endogenous insulin deficiency (fasting serum C-peptide immunoreactivity <0.6 ng/mL) at the last observed point in time. When a patient fulfills only (1) and (2), but not (3), he/she is diagnosed with 'SPIDDM (probable)' because the diabetes is non-insulin-dependent type.

New diagnostic criteria (2023) for slowly progressive type 1 diabetes (SPIDDM): Report from Committee on Type 1 Diabetes in Japan Diabetes Society (English version)

The diagnostic criteria for slowly progressive type 1 diabetes (slowly progressive insulin-dependent diabetes mellitus; SPIDDM) have been revised by the Committee on Type 1 Diabetes of the Japan Diabetes Society. All of the following three criteria must be met for "a definitive diagnosis of SPIDDM": (1) presence of anti-islet autoantibodies at some point in time during the disease course; (2) absence of ketosis or ketoacidosis at the diagnosis of diabetes with no requirement of insulin treatment to correct hyperglycemia immediately after diagnosis in principle; and (3) gradual decrease of insulin secretion over time, with insulin treatment required at more than 3 months after diagnosis, and presence of severe endogenous insulin deficiency (fasting serum C-peptide immunoreactivity < 0.6 ng/mL) at the last observed point in time. When a patient fulfills the only (1) and (2), but not (3), he/she is diagnosed with "SPIDDM (probable)" because the diabetes is non-insulin-dependent state.

Quality of life after total pancreatectomy with islet autotransplantation for chronic pancreatitis in Japan

BACKGROUND

Patients with chronic pancreatitis (CP) often have severe and intractable abdominal pain, leading to decreased quality of life (QOL), inability to work or attend school, and increased health care costs due to repeated emergency room visits and hospitalizations.

METHODS

We evaluated the efficacy of total pancreatectomy and islet autotransplantation (TPIAT) in terms of pain control and QOL in CP patients treated at our center in Japan. To evaluate QOL, we used the Short-Form 36 Health Survey version 2 (SF-36v2_® Standard, Japanese), European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 (EORTC QLQ-C30), and Quality of Life Questionnaire-Pancreatic Modification (QLQ-PAN28).

RESULTS

Between August 2016 and June 2019, we performed this procedure in 5 patients. All patients were followed up for 12 months and all transplanted islets were still functioning at the 1-year follow-up. The major adverse events were abdominal wall hemorrhage, intestinal obstruction, intra-abdominal abscess, and abdominal pain requiring hospitalization; no case had sequelae. No major complications were due to islet transplantation. Pain scores improved postoperatively in all patients. Three QOL item dimensions role-physical (p = 0.03125), general health perception (p = 0.03125) and vitality (p = 0.03125) in the SF-36 were significantly improved 12 months after TPIAT. Mean values of many other QOL items improved, though not significantly.

CONCLUSION

The QOL improvement after TPIAT for CP suggests its effectiveness in the Japanese population.

Negative correlation between organ heteroplasmy, particularly hepatic heteroplasmy, and age at death revealed by post-mortem studies of m.3243A > G cases

Mitochondrial DNA m.3243A > G mutation causes mitochondrial encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) and its associated multi-organ disorders, including diabetes. To clarify associations between m.3243A > G organ heteroplasmy and clinical phenotypes, including the age at death, we combined genetic and pathological examinations from seven unreported and 36 literature cases of autopsied subjects. Clinical characteristics of subjects were as follows: male, 13; female, 28; unknown, 2; the age at death, 36.9 ± 20.2 [4-82] years; BMI, 16.0 ± 2.9 [13.0-22.3]; diabetes, N = 21 (49%), diabetes onset age 38.6 ± 14.2 years; deafness, N = 27 (63%); stroke-like episodes (StLEp), N = 25 (58%); congestive heart failure (CHF), N = 15 (35%); CHF onset age, 51.3 ± 14.5 years. Causes of death (N = 32) were as follows: cardiac, N = 13 (41%); infection, N = 8 (25%); StLEp, N = 4 (13%); gastrointestinal, N = 4 (13%); renal, N = 2 (6%); hepatic, N = 1 (2%). High and low heteroplasmies were confirmed in non-regenerative and regenerative organs, respectively. Heteroplasmy of the liver, spleen, leukocytes, and kidney for all subjects was significantly associated with the age at death. Furthermore, the age at death was related to juvenile-onset (any m.3243A > G-related symptoms appeared before 20) and stroke-like episodes. Multiple linear regression analysis with the age at death as an objective variable showed the significant contribution of liver heteroplasty and juvenile-onset to the age at death. m.3243A > G organ heteroplasmy levels, particularly hepatic heteroplasmy, are significantly associated with the age at death in deceased cases.

In vivo relationship between bound and free insulin in patients with diabetes having anti-insulin antibodies

Objective

The Scatchard plot of anti-insulin antibodies is curvilinear, indicating heterogeneity in binding sites. However, the relationship between bound insulin (B) and free insulin (F) in patients with anti-insulin antibodies has not yet been elucidated. This study aimed to determine this relationship.

Methods

We studied two insulin-treated patients with diabetes who had high titers of anti-insulin antibodies. The B and F levels were measured using daily blood samples. Assuming that the law of mass action is applicable to the reactions between insulin and anti-insulin antibody forms, we plotted the bound-to-free ratio (B/F) vs. B using patient data. We also performed an equilibrium binding assay in vitro.

Results

Some of the B/F vs. B plots of the daily variation showed an approximately linear relationship, while the Scatchard plots of in vitro data became curvilinear.

Conclusion

Our study suggests that the one-site (high-affinity site) of anti-insulin antibodies accounts, for the most part, for insulin pharmacokinetics within physiological insulin concentrations.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13340-023-00641-1.

Bivalent GAD autoantibody ELISA improves clinical utility and risk prediction for adult autoimmune diabetes

AIM/INTRODUCTION

To investigate the differences in the clinical significance and glutamic acid decarboxylase autoantibody (GADA) affinity between RIA (RIA-GADA) and ELISA (ELISA-GADA) in patients with type 1 diabetes.

METHODS

A total of 415 patients with type 1 diabetes were enrolled, including 199 acute-onset type 1 diabetes, 168 slowly progressive type 1 diabetes (SPIDDM), and 48 fulminant type 1 diabetes. GADA affinity was measured by a competitive binding experiment using unlabeled recombinant human GAD65 protein, and the diagnostic performance of both assays and the relationship between GADA affinity and the decline of fasting C-peptide (F-CPR) were examined.

RESULTS

While the ELISA-GADA displayed a higher sensitivity than the RIA method in diagnosing type 1 diabetes in acute-onset patients, about 40% of SPIDDM patients with low-titer RIA-GADA were determined as negative by the ELISA method. Patients with type 1 diabetes with RIA-GADA alone had an older age of onset, less diabetic ketoacidosis, a higher BMI, and a higher F-CPR compared with patients positive for both RIA-GADA and ELISA-GADA. Additionally, 36% of RIA-GADA-positive patients had low-affinity GADA (<10¹⁰  L/mol), which was significantly higher than in the ELISA-GADA-positive patients (4%, P < 0.0001). Furthermore, over a 3 year monitoring period, F-CPR levels decreased in ELISA-GADA-positive SPIDDM, whereas it was maintained in patients with RIA-GADA alone, regardless of GADA affinity.

CONCLUSIONS

These results suggest that bivalent ELISA for GADA is superior to the RIA method in diagnosing type 1 diabetes. Moreover, the diagnostic superiority of the ELISA-GADA made possible the concurrent identification of SPIDDM patients at high-risk of early progression, and allowed for more accurate clinical diagnosis and management.

Graft failure after allogeneic islet transplantation in a patient with type 1 diabetes and a high anti-glutamic acid decarboxylase antibody titer

Pancreatic islet transplantation is a β-cell replacement therapy for people with insulin-deficient diabetes who have difficulty in glycemic control and suffer from frequent severe hypoglycemia. However, the number of islet transplantations carried out is still limited in Asia. We report a case of allogeneic islet transplantation in a 45-year-old Japanese man with type 1 diabetes. Although the islet transplantation was successfully carried out, graft loss was observed on the 18th day. Immunosuppressants were used in accordance with the protocol, and donor-specific anti-human leukocyte antigen antibodies were not detected. Autoimmunity relapse was also not observed. However, the patient had a high titer of anti-glutamic acid decarboxylase antibody from before the islet transplantation, and autoimmunity might thus have affected the β-cells in the transplanted islet. The evidence is still scarce to reach conclusions, and further data accumulation is required to enable proper patient selection before islet transplantation.

Comparing the clinical significance and antigen specificity of insulinoma-associated antigen-2 autoantibodies between radioimmunoassay and enzyme-linked immunosorbent assay in Japanese patients with type 1 diabetes

AIMS/INTRODUCTION

This study aimed to investigate the clinical significance and antigen specificity of autoantibodies to insulinoma-associated antigen-2 (IA-2A) by radioimmunoassay (RIA; IA-2A-RIA) and enzyme-linked immunosorbent assay (ELISA; IA-2A-ELISA) in Japanese patients with type 1 diabetes.

MATERIALS AND METHODS

A total of 338 type 1 diabetic patients were enrolled, including 38 fulminant type 1 diabetes, 168 acute-onset type 1 diabetes and 137 slowly-progressive type 1 diabetes (SPIDDM). The concordance, correlation of autoantibody titer, and the relationship between IA-2A and progression to the insulin-deficient state were examined. Also, competitive assay was used to examine the antigen specificity.

RESULTS

The prevalence of IA-2A-ELISA was 4-5% lower than that of IA-2A-RIA in both the acute-onset type 1 diabetes and SPIDDM, but the diagnostic sensitivities of both subtypes, when measured in combination with glutamic acid decarboxylase autoantibody, were comparable. The diagnosis of type 1 diabetes using either the RIA or ELISA methods showed substantial agreement with the exponential correlation of autoantibody titers detected by RIA and ELISA. Among the SPIDDM patients, the fasting C-peptide for IA-2A-positive cases by ELISA, but not the RIA method, was significantly lower than in the negative cases (P < 0.05). Furthermore, IA-2A-ELISA proved superior to the RIA method in predicting the progression to insulin deficiency in SPIDDM. Competitive analysis showed that even sera with discrepant results by RIA and ELISA have IA-2-specific autoantibodies.

CONCLUSION

These results suggest that IA-2A-ELISA is a reliable marker not only for the diagnosis of type 1 diabetes, but also for the prediction of future insulin dependency; that is, detection of IA-2A-ELISA helps identify a subtype of SPIDDM patients who would likely progress onto insulin-deficient state.

Perioperative C-peptide index is associated with the status of diabetes management after pancreatectomy

Aims/Introduction

This study aimed to identify the clinical factors affecting postoperative residual pancreatic β‐cell function, as assessed by the C‐peptide index (CPI), and to investigate the association between perioperative CPI and the status of diabetes management after pancreatectomy.

Materials and Methods

The associations between perioperative CPI and clinical background, including surgical procedures of pancreatectomy, were analyzed in 47 patients who underwent pancreatectomy, and were assessed for pre‐and postoperative CPI. The association between perioperative CPI and glycemic control after pancreatectomy was investigated.

Results

The low postoperative CPI group (CPI <0.7) had longer duration of diabetes (17.5 ± 14.5 vs 5.5 ± 11.0 years, P = 0.004), a higher percentage of sulfonylurea users (41.7 vs 8.7%, P = 0.003) and a greater number of drug categories used for diabetes treatment (1.9 ± 1.1 vs 0.8 ± 0.8, P <0.001) than did the high postoperative CPI group. Postoperative CPI was higher (1.4 ± 1.2 vs 0.7 ± 0.6, P = 0.039) in patients with low glycosylated hemoglobin (<7.0%) at 6 months after pancreatectomy; preoperative (2.0 ± 1.5 vs 0.7 ± 0.5, P = 0.012) and postoperative CPI (2.5 ± 1.4 vs 1.4 ± 1.1, P = 0.020) were higher in non‐insulin users than in insulin users at 6 months after surgery.

Conclusions

The duration of diabetes and preoperative diabetes treatment were associated with residual pancreatic β‐cell function after pancreatectomy. Furthermore, perioperative β‐cell function as assessed by CPI was associated with diabetes management status after pancreatectomy.

Fragmented QRS on electrocardiography as a predictor for diastolic cardiac dysfunction in type 2 diabetes

Aims/Introduction

Diastolic cardiac dysfunction in type 2 diabetes (DD2D) is a critical risk of heart failure with preserved ejection fraction. However, there is no established biomarker to detect DD2D. We aimed to investigate the predictive impact of fragmented QRS (fQRS) on electrocardiography on the existence of DD2D.

Materials and Methods

We included in‐hospital patients with type 2 diabetes without heart failure symptoms who were admitted to our institution for glycemic management between November 2017 and April 2021. An fQRS was defined as an additional R′ wave or notching/splitting of the S wave in two contiguous electrocardiography leads. DD2D was diagnosed according to the latest guidelines of the American Society of Echocardiography.

Results

Of 320 participants, 122 patients (38.1%) had fQRS. DD2D was diagnosed in 82 (25.6%). An fQRS was significantly associated with the existence of DD2D (odds ratio 4.37, 95% confidence interval 2.33–8.20; p < 0.0001) adjusted for seven potential confounders. The correlation between DD2D and diabetic microvascular disease was significant only among those with fQRS. Classification and regression tree analysis showed that fQRS was the most relevant optimum split for DD2D.

Conclusions

An fQRS might be a simple and promising predictor of the existence of DD2D. The findings should be validated in a larger‐scale cohort.

Fulminant type 1 diabetes patients display high frequencies of IGRP-specific type 1 CD8+ T cells

The role of cellular autoimmunity in the pathogenesis of fulminant type 1 diabetes (FT1D) remains largely unknown. In this study, we performed an integrated assay using peripheral blood mononuclear cells to determine the islet antigen-specific CD8⁺ T cell responses in FT1D and compare the responses among acute-onset T1D (AT1D) and slowly progressive T1D (SP1D). IGRP- and ZnT8-specific IL-6, G-CSF, and TNF-α responses were significantly upregulated in patients with FT1D, while IGRP- and ZnT8-specific IP-10 responses were significantly upregulated in patients with AT1D than in non-diabetics (ND). Furthermore, the frequencies of IGRP-specific type 1 CD8⁺ cytotoxic T (Tc1) cells were significantly higher in the FT1D group than in the ND, SP1D, and AT1D groups. Additionally, IGRP-specific Tc1 cells were more abundant in the FT1D with HLA-A2 group than in the FT1D without A2 group. In conclusion, our study suggests that IGRP-specific CD8⁺ T cells significantly contribute to the pathogenesis of FT1D.

Allogeneic islet transplantation with monitoring of islet-specific cellular autoimmunity in a Japanese patient with type 1 diabetes: a case report

Here, we report a case of allogeneic islet transplantation in Japan. A 48-year-old man received intraportal islet transplantation (5,945 islet equivalent/kg), and stabilization of blood glucose levels and suppression of hypoglycemia were achieved. In this case, we used our original assessment method to detect the responses of the recipient's T cells to islet autoantigens over time to monitor cellular autoimmunity. Other markers could not predict graft dysfunction in advance, but our method detected the activation of islet antigen-specific CD8⁺ T cell responses before the deterioration of pancreatic beta cell function, indicating the possibility of the non-invasive detection of pancreatic beta cell damage due to recurrent autoimmunity.

High prevalence of fragmented QRS on electrocardiography in Japanese patients with diabetes irrespective of metabolic syndrome

AIMS/INTRODUCTION

Fragmented QRS (fQRS) on electrocardiography is a marker of myocardial fibrosis and myocardial scar formation. This study aimed to clarify the relationship of fQRS with diabetes mellitus and metabolic syndrome (MetS) in Japanese patients.

MATERIALS AND METHODS

Approximately 702 individuals who had a routine health checkup at the Hokuriku Health Service Association (Toyama, Japan) in October 2014 were enrolled and categorized into one of the following four groups based on MetS and diabetes mellitus status: with diabetes mellitus (+) MetS+ (164 participants); diabetes mellitus+ without MetS (Mets-; 103 participants); diabetes mellitus- MetS+ (133 participants); and diabetes mellitus- MetS- (302 participants). fQRS was assessed using the results of electrocardiography.

RESULTS

The prevalence of fQRS was statistically higher in patients with diabetes mellitus+ MetS+ (37%) and diabetes mellitus+ MetS- (35%), than those with diabetes mellitus- MetS+ (14%) or diabetes mellitus- MetS- (10%; P < 0.0001). Significant differences were observed between the fQRS(+) and fQRS(-) groups for age, sex, waist circumference, heart rate, hypertension, hemoglobin A1c, total cholesterol, MetS and diabetes mellitus. The area under the receiver operating characteristic curve for traditional risk factors and diabetes mellitus was 0.72 (P = 0.0007, 95% confidence interval 0.67-0.76), and for traditional risk factors and MetS it was 0.67 (P = 0.28, 95% confidence interval 0.62-0.72). Patients with diabetes mellitus had more than threefold higher likelihood of showing fQRS (odds ratio 3.41; 95% confidence interval 2.25-5.22; P < 0.0001) compared with the reference group without diabetes mellitus, after adjusting for age, sex, dyslipidemia, hypertension and waist circumference.

CONCLUSIONS

fQRS was observed more frequently in diabetes mellitus patients than in MetS and control individuals. Diabetes mellitus was the most significant determinant for fQRS among MetS and other traditional metabolic risk factors.

Diastolic Cardiac Function Improvement by Liraglutide Is Mainly Body Weight Reduction Dependent but Independently Contributes to B-Type Natriuretic Peptide Reduction in Patients with Type 2 Diabetes with Preserved Ejection Fraction

OBJECTIVES

A single-arm prospective study was conducted among Japanese patients with type 2 diabetes having preserved ejection fraction. The aim was to investigate (1) whether liraglutide therapy could improve B-type natriuretic peptide (BNP) levels and diastolic cardiac function assessed by the E-wave to E' ratio (E/E') using transthoracic echocardiography (TTE), and (2) whether E/E' contributed to BNP improvement independent of bodyweight reduction (UMIN000005565).

METHODS

Patients with type 2 diabetes and left ventricular ejection fraction (LVEF) ≥ 40% without heart failure symptoms were enrolled, and daily injection with liraglutide (0.9 mg) was introduced. Cardiac functions were assessed by TTE before and after 26 weeks of liraglutide treatment. Diastolic cardiac function was defined as septal E/E' ≥ 13.0.

RESULTS

Thirty-one patients were analyzed. BNP and E/E' improved, with BNP levels declining from 36.8 ± 30.5 pg/mL to 26.3 ± 25.9 pg/mL (p = 0.0014) and E/E' dropping from 12.7 ± 4.7 to 11.0 ± 3.3 (p = 0.0376). The LVEF showed no significant changes. E/E' improved only in patients with E/E' ≥ 13.0. Favorable changes in E/E' were canceled when adjusted for body mass index (BMI). Multivariate linear regression analysis revealed that the left ventricular diastolic diameter and ∆E/E'/∆BMI contributed to ∆BNP/baseline BNP (p = 0.0075, R ² = 0.49264).

CONCLUSIONS

Liraglutide had favorable effects on BNP and E/E' but not on LVEF. E/E' improvement was only seen in patients with diastolic cardiac function. Body weight reduction affected the change of E/E'. The BMI-adjusted E/E' significantly contributed to the relative change of BNP. GLP-1 analog treatment could be considered a therapeutic option against diabetic diastolic cardiac dysfunction regardless of body weight. This trial is registered with the University Hospital Medical Information Network in Japan, with clinical trial registration number: UMIN000005565.

Distinct Phenotypes of Islet Antigen-Specific CD4+ T Cells Among the 3 Subtypes of Type 1 Diabetes

CONTEXT

Type 1 diabetes (T1D) is classified into 3 subtypes: acute-onset (AT1D), slowly progressive (SP1D), and fulminant (FT1D). The differences in the type of cellular autoimmunity within each subtype remain largely undetermined.

OBJECTIVE

To determine the type and frequency of islet antigen-specific CD4+ T cells in each subtype of T1D.

PARTICIPANTS

Twenty patients with AT1D, 17 with SP1D, 18 with FT1D, and 17 persons without diabetes (ND).

METHODS

We performed an integrated assay to determine cellular immune responses and T-cell repertoires specific for islet antigens. This assay included an ex vivo assay involving a 48-hour stimulation of peripheral blood mononuclear cells with antigen peptides and an expansion assay involving intracytoplasmic cytokine analysis.

RESULTS

The results of the ex vivo assay indicated that glutamic acid decarboxylase 65 (GAD65)-specific interleukin-6 and interferon-inducible protein-10 (IP-10) responses and preproinsulin (PPI)-specific IP-10 responses were significantly upregulated in AT1D compared with those of ND. Furthermore, GAD65- and PPI-specific granulocyte colony-stimulating factor responses were significantly upregulated in FT1D. Expansion assay revealed that GAD65- and PPI-specific CD4+ T cells were skewed toward a type 1 helper T (Th1)- cell phenotype in AT1D, whereas GAD65-specific Th2 cells were prevalent in SP1D. GAD65-specific Th1 cells were more abundant in SP1D with human leukocyte antigen-DR9 than in SP1D without DR9. FT1D displayed significantly less type 1 regulatory T (Tr1) cells specific for all 4 antigens than ND.

CONCLUSIONS

The phenotypes of islet antigen-specific CD4+ T cells differed among the three T1D subtypes. These distinct T-cell phenotypes may be associated with the manner of progressive β-cell destruction.

Maturity-Onset diabetes of the young type 5 treated with the glucagon-like peptide-1 receptor agonist: A case report

RATIONALE

Maturity-onset diabetes of the young type 5 (MODY 5) is a form of monogenic diabetes that is often accompanied by pancreatic dysfunction. To date, no cases of MODY 5 treated with glucagon-like peptide-1 receptor agonist (GLP-1RA) have been reported. We present the first case of MODY 5 treated with GLP-1RA.

PATIENT CONCERNS

A 17-year-old woman, with a history of being operated for congenital ileal atresia at birth, was admitted to our hospital due to hyperglycemia. She had been clinically diagnosed with type 1 diabetes 1 month prior, and administered 14 units of insulin glargine 300 U/mL per day.

DIAGNOSIS

She had hypopotassemia, hypomagnesaemia, pancreatic body, and tail defects, multiple renal cysts, and a family history of diabetes, and urogenital anomaly. Genetic testing revealed heterozygous deletion of hepatocyte nuclear transcription factor-1 beta, leading to the diagnosis of MODY 5.

INTERVENTIONS

The patient was treated with multiple daily insulin injections for 9 days (22 units/d) before administration of GLP-1RA, and then liraglutide was initiated.

OUTCOMES

Liraglutide treatment (0.6 mg/d) alone maintained the patient's glycated hemoglobin level below 7.0% for at least 12 months after discharge. A higher dose, 0.9 mg/d, of liraglutide was not tolerated by the patient due to nausea. Serum levels of C-peptide immunoreactivity were 1.15 ng/mL and 1.91 ng/mL, respectively, after 6 and 12 months of liraglutide therapy.

LESSONS

GLP-1RA might be effective at regulating glucose metabolism by utilizing residual pancreatic endocrine function in patients with MODY 5. Imaging and genetic screening were helpful in the diagnosis of MODY 5.

Patient Satisfaction and Clinical Efficacy of Flash Glucose Monitoring in Patients with Type 1 Diabetes: A Prospective, Single-Center, Single-Arm Study

INTRODUCTION

Frequent self-monitoring of blood glucose (SMBG) is usually required in patients with type 1 diabetes (T1D). However, the fear of self-testing, hygiene, and social obstacles may deter some patients from SMBG. Flash glucose monitoring (FGM), a less-invasive glucose monitoring method, was launched in Japan in September 2017. The aim of this study was to evaluate patient satisfaction and the clinical efficacy of FGM in Japanese patients with T1D.

METHODS

Patient satisfaction with FGM was assessed using the Diabetes Treatment Satisfaction Questionnaire (DTSQ) and Diabetes Therapy-Related Quality of Life (DTR-QOL) questionnaire before (baseline) and 4 and 12 weeks after initiating FGM use in 20 Japanese patients with T1D. Clinical parameters related to glucose metabolism, such as glycated hemoglobin (HbA1c) levels, were assessed, and glucose fluctuations were evaluated using the FGM data. Values at 4 and 12 weeks after initiating FGM were compared with baseline data using the Wilcoxon signed-rank test. The mean absolute relative difference (MARD) between glucose values detected using the FGM device and by SMBG was also calculated.

RESULTS

The DTSQ scores significantly improved 12 weeks after initiating FGM (P < 0.001). The DTR-QOL scores related to "burden in social activities" and "treatment satisfaction" also significantly improved 12 weeks after initiating FGM (P = 0.024 and 0.007, respectively). The HbA1c values and the percentage of time within the target glucose range (3.9-7.8 mmol/L) at the 12-week time point also improved, from 58 ± 5 (baseline) to 54 ± 4 mmol/mol (P = 0.002) and from 36% (interquartile range [IQR] 25-44.5%) (baseline) to 43% (IQR 39-50%) (P = 0.016), respectively. The MARD between glucose values detected using FGM and those detected using SMBG was 12.2% throughout the study period.

CONCLUSIONS

Flash glucose monitoring contributed to improved patient satisfaction and the adjustment of blood glucose levels in patients with T1D.

TRIAL REGISTRATION

University Hospital Medical Information Network Clinical Trials Registry (UMIN-CTR): UMIN000029673.

Clinical manifestations of a sporadic maturity-onset diabetes of the young (MODY) 5 with a whole deletion of HNF1B based on 17q12 microdeletion

We report a sporadic case of maturity-onset diabetes of the young type 5 (MODY5) with a whole-gene deletion of the hepatocyte nuclear factor-1beta (HNF1B) gene. A 44-year-old Japanese man who had been diagnosed with early-onset non-autoimmune diabetes mellitus at the age of 23 was examined. He showed multi-systemic symptoms, including a solitary congenital kidney, pancreatic hypoplasia, pancreatic exocrine dysfunction, elevation of the serum levels of liver enzymes, hypomagnesemia, and hyperuricemia. These clinical characteristics, in spite of the absence of a family history of diabetes, prompted us to make the diagnosis of maturity-onset diabetes of the young 5 (MODY 5). One allele deletion of the entire HNF1B gene revealed by multiplex ligation-dependent probe amplification (MLPA) led us to the diagnoses of 17q12 microdeletion syndrome even though there were negative chromosomal analyses with array comparative genomic hybridization (CGH). 17q12 microdeletion syndrome, which is not rare especially in sporadic cases since 17q12 is a typical hot spot for chromosomal deletion, could have complicated the clinical heterogeneity of MODY5.

Variants in the BACH2 and CLEC16A gene might be associated with susceptibility to insulin-triggered type 1 diabetes

AIM/INTRODUCTION

Insulin administration was found to trigger type 1 diabetes in six Japanese type 2 diabetes patients with type 1 diabetes high-risk human leukocyte antigen class II and the class I allele of the insulin gene variable number tandem repeat genotype. The objective of the present study was to assess the contribution of non-human leukocyte antigen single-nucleotide polymorphisms (SNPs) to the risk of developing insulin-triggered type 1 diabetes.

MATERIALS AND METHODS

We genotyped 13 type 1 diabetes susceptible SNPs in six patients and compared them with those in Japanese controls (Hap Map3-JPT). The SNPs that showed statistically significant results were further analyzed using non-diabetic control participants and participants with type 2 diabetes at the Ehime University Hospital.

RESULTS

The risk allele frequency of BACH2 rs3757247 in the six patients was significantly more frequent than that in 86 Japanese controls (P = 0.038). No significant difference in the allele frequency was observed in the other SNPs. This result was confirmed by the findings that the risk allele frequency of BACH2 in the six patients was significantly higher than that in the non-diabetic control participants (n = 179) and type 2 diabetes with or without insulin treatment (n = 154 or n = 152; P = 0.035, 0.034 or 0.037, respectively). Despite being statistically not significant, the six patients were all homozygous for the CLEC16A rs12708716 risk allele and five were homozygous for the CLEC16A rs2903692 risk allele.

CONCLUSIONS

In addition to type 1 diabetes high-risk human leukocyte antigen class II and the class I allele of the insulin gene variable number tandem repeat genotype, the possibility that the risk variants of BACH2 and CLEC16A could contribute to the development of insulin-triggered type 1 diabetes cannot be excluded.

Tacrolimus-induced diabetic ketoacidosis with subsequent rapid recovery of endogenous insulin secretion after cessation of tacrolimus: A case report with review of literature

RATIONALE

Immunosuppressive agents such as tacrolimus (TAC) and cyclosporin might cause glycemic disorders by suppressing insulin production. However, only a few cases of diabetic ketoacidosis (DKA) with longitudinal evaluation of endogenous insulin secretion related to TAC administration have been reported.

PATIENT CONCERNS

A 59-year-old Asian woman, who received prednisolone and TAC 4.0 mg for the treatment of anti-aminoacyl-tRNA synthetase antibody-positive interstitial pneumonia, was admitted to our hospital due to impaired consciousness and general malaise.

DIAGNOSES

She had metabolic acidosis; her plasma glucose, fasting serum C-peptide immunoreactivity (CPR), and urinary CPR levels were 989 mg/dL (54.9 mmol/L), 0.62 ng/mL, and 13.4 μg/d, respectively. No islet-related autoantibodies were detected. Therefore, she was diagnosed with TAC-induced DKA.

INTERVENTION

Intravenous continuous insulin infusion and rapid saline infusion were administered. TAC was discontinued because of its diabetogenic potential.

OUTCOMES

Sixteen weeks after cessation of TAC administration, she showed good glycemic control without administration of insulin or any oral hypoglycemic agents; her serum CPR level also improved dramatically. These findings suggested that TAC-induced pancreatic beta cell toxicity is reversible.

LESSONS

We reported a case of TAC-induced DKA with subsequent recovery of pancreatic beta cell function after cessation of TAC, resulting in good glycemic control. As TAC is widely used, we should pay attention to patients' glucose levels even though the TAC concentrations used are within the target range. Furthermore, dose reduction or cessation of TAC should be considered if hyperglycemia is detected during administration of this agent.

Poorly controlled type 2 diabetes with no progression of diabetes-related complications and low levels of advanced glycation end products: A Case report

RATIONALE

Previous studies have suggested that increased levels of advanced glycation end products (AGEs) and soluble receptor for AGE (sRAGE) are associated with diabetes-related complications. However, there is little evidence on the association between long-term levels of AGEs and sRAGE and progression of diabetes-related complications.

PATIENT CONCERNS

A 64-year-old man had poorly controlled type 2 diabetes, obesity, smoking, hypertension, and dyslipidemia. He had many risk factors for diabetes-related complications.

DIAGNOSIS

Despite poor glycemic control over 15 years, the patient did not exhibit diabetes-related complications.

INTERVENTIONS

We examined serum AGEs (CEL and MG-H1) and sRAGE levels in this patient over the past 10 years.

OUTCOMES

The patient maintained low serum AGEs and sRAGE levels.

LESSONS

AGEs and sRAGE levels may be associated with long-term development of diabetes-related complications.

Evaluation of cellular and humoral autoimmunity before the development of type 1 diabetes in a patient with idiopathic CD4 lymphocytopenia

A 64-year-old woman developed type 1 diabetes 23 years after the diagnosis of idiopathic CD4 lymphocytopenia. To investigate the etiological interaction between idiopathic CD4 lymphocytopenia and type 1 diabetes, we carried out a longitudinal analysis related to islet-specific autoimmunity. Anti-glutamic acid decarboxylase antibody had been already weakly positive for at least 16 years and started rising at 6 months before the onset of type 1 diabetes. The seroconversion of anti-insulinoma-associated antigen-2 antibody and insulin autoantibody occurred at the time of onset. The ratio of CD8/CD4 had been gradually increasing for 8 years before type 1 diabetes onset. Notably, islet-specific glucose-6-phosphatase catalytic subunit-related protein-reactive CD8+ T cells were detected at type 1 diabetes onset, and the frequency was higher than that in 15 non-diabetic controls (6.75% vs 0.49 ± 0.78%, mean ± SD). The present type 1 diabetes patient, presented with idiopathic CD4 lymphocytopenia and showed an elevated number of CD8+ T cells, including the islet antigen-specific CD8+ T cells that might contribute to autoimmune destruction of pancreatic β-cells.

Contribution of pancreatic α-cell function to insulin sensitivity and glycemic variability in patients with type 1 diabetes

AIMS/INTRODUCTION

To evaluate the contribution of pancreatic α-cell function to the dawn phenomenon, insulin sensitivity, hepatic glucose uptake and glycemic variability in patients with type 1 diabetes.

MATERIALS AND METHODS

In 40 patients with type 1 diabetes, arginine stimulation tests were carried out, and the area under the curve (AUC) of glucagon was measured using radioimmunoassays (AUCglc RIA ) and enzyme-linked immunosorbent assays (AUCglc ELISA ). The ratio of the insulin dose delivered by an artificial pancreas to maintain euglycemia between 04.00 and 08.00 hours or between 00.00 and 04.00 hours was measured as the dawn index. The glucose infusion rate and hepatic glucose uptake were measured using hyperinsulinemic euglycemic clamp and clamp oral glucose loading tests. Glycemic variability in 96 h was measured by continuous glucose monitoring.

RESULTS

The median dawn index (1.7, interquartile range 1.0-2.8) was not correlated with AUCglc RIA (R2  = 0.03, P = 0.39) or AUCglc ELISA (R2  = 0.04, P = 0.32). The median glucose infusion rate (7.3 mg/kg/min, interquartile range 6.4-9.2 mg/kg/min) was significantly correlated with AUCglc RIA (R2  = 0.20, P = 0.02) and AUCglc ELISA (R2  = 0.21, P = 0.02). The median hepatic glucose uptake (65.3%, interquartile range 40.0-87.3%) was not correlated with AUCglc RIA (R2  = 0.07, P = 0.26) or AUCglc ELISA (R2  = 0.26, P = 0.79). The standard deviation of glucose levels measured by continuous glucose monitoring was significantly correlated with AUCglc RIA (R2  = 0.11, P = 0.049), but not with AUCglc ELISA (R2  = 0.01, P = 0.75).

CONCLUSIONS

Pancreatic α-cell function contributed to insulin sensitivity in patients with type 1 diabetes.

C-Peptide Area Under the Curve at Glucagon Stimulation Test Predicts Glucose Improvements by GLP-1 Receptor Analogue: A Retrospective Observational Study

INTRODUCTION

Despite the widespread use of glucagon-like peptide-1 (GLP-1) receptor agonists (GLP-1ras) to improve glycemic regulation, with a low risk of hypoglycemia and weight reduction, their effectiveness varies among individuals. This study aimed to identify predictors of the efficacy of GLP-1ra on Hemoglobin A1c (HbA1c) in patients with insulin-independent diabetes.

METHODS

In total, 58 patients with insulin-independent diabetes were included. Patients were included if their β-cell function was evaluated via a glucagon stimulation test (GST) before the introduction of GLP-1ra therapy. β-Cell function-related indices, such as the C-peptide index (CPI), increments in C-peptide immunoreactivity (CPR) after glucagon stimulation (ΔCPR), and the area under the CPR curve (CPR-AUC) during the GST, were evaluated. HbA1c and body weight (BW) were measured at 6 and 12 months after the initiation of GLP-1ra.

RESULTS

A univariate regression analysis revealed a significant correlation between CPR-AUC and changes in HbA1c at 6 months and with changes in BW at 6 and 12 months. A multivariate regression analysis revealed that CPR-AUC was significantly correlated with changes in HbA1c at 6 months. A receiver-operating characteristic analysis revealed that 21.9 ng/ml·min CPR-AUC was the optimal cut-off value to predict an HbA1c level < 7%, i.e., 53 mmol/mol.

CONCLUSION

Residual β-cell function, as assessed via CPR-AUC in the GST, is an effective predictor of the efficacy of GLP-1ras.

Response to "Preserved" glucagon secretion in fulminant type 1 diabetes

We compared the glucagon responses to arginine stimulation in five patients with fulminant type 1 diabetes and five age- and diabetes duration-matched acute-onset type 1 diabetes, and the curves of the glucagon responses were similar. In our study, we measured the glucagon levels by not only radioimmunoassay, but also novel enzyme-linked immunosorbent assay.

Efficacy and safety of liraglutide added to insulin therapy in elderly patients with type 2 diabetes

INTRODUCTION

The combination of GLP-1 receptor agonists and insulin is effective in type 2 diabetes (T2D) treatment. However, its longitudinal efficacy and safety in elderly patients have not been established. We evaluated whether liraglutide (Lira) added to insulin therapy safely improved glycaemic control in T2D patients aged >65 years.

METHODS

Twenty T2D patients receiving insulin were recruited, and Lira was added to their treatment regimen. Before and 6 months after Lira was added, we assessed the metabolic parameters and continuous glucose monitoring (CGM) data.

RESULTS

Six months after Lira was added, the levels of HbA1c and glycated albumin and body weight were significantly improved, despite the daily doses and number of insulin injections per day being reduced. CGM analysis revealed that the SD and AUC of glucose >180 mg/dL were significantly decreased; the proportion of hypoglycaemic events was not increased.

CONCLUSION

Lira administration safely improved glycaemic control and reduced body weight. Lira added to insulin therapy may improve the quality of life in elderly T2D patients undergoing insulin therapy, especially those requiring social support.

Durability of Glucose-Lowering Effect of the First Administration of Dulaglutide: A Retrospective, Single-Center, Single-Arm Study

INTRODUCTION

Dulaglutide (Dula) is a once-weekly glucagon-like peptide-1 receptor agonist that efficiently reduces the level of glycated hemoglobin (HbA1c) in patients with type 2 diabetes (T2D). However, the durability of the glucose-lowering effect of the first injection of Dula (1st Dula) remains unclear.

METHODS

This study had a retrospective, single-center, and single-arm design in a clinical setting and was conducted between April 2016 and March 2017. We investigated the changes and fluctuations in glucose level in 15 patients with T2D using a continuous glucose monitor, from 1 day before the first administration of Dula to 6 days thereafter.

RESULTS

The mean glucose levels decreased significantly from 1 day before 1st Dula up to 5 days thereafter, whereas the standard deviation, mean amplitude of glucose excursion, and percentage of the glucose levels > 180 mg/dL were significantly improved only up to 3, 2, and 3 days after the 1st Dula, respectively, compared to those before administration.

CONCLUSION

The effect of blood glucose regulation after the 1st Dula did not continue for a whole week. These effects should be considered when adjusting for other hypoglycemic agents.

High frequency of type 2 diabetes and impaired glucose tolerance in Japanese subjects with the angiopoietin-like protein 8 R59W variant

BACKGROUND

Angiopoietin-like protein 8 (ANGPTL8) is considered to be metabolically multifunctional. One notable function still to be elucidated definitively is a betatrophic role in protecting and preserving pancreatic beta-cell function. There is, however, a paucity of data regarding the role of ANGPTL8 in the etiology of type 2 diabetes (T2D), but some findings of human research have suggested the potential for significant involvement.

OBJECTIVE

To examine the frequency of T2D and impaired glucose tolerance (IGT) in Japanese subjects with the ANGPTL8 R59W variant.

METHODS

ANGPTL8 R59W (Rs2278426, c.194C > T) was determined by polymerase chain reaction-restriction fragment length polymorphism using the restriction enzyme FokI in 797 consecutive Japanese individuals. Subjects with triglyceride levels greater than or equal to 150 mg/dL were considered to be hypertriglyceridemic.

RESULTS

Genotype frequencies of ANGPTL8 R59W were as follows: wild-type RR (C/C) 53.5%, RW (C/T) 36.6%, and WW (T/T) 9.9%. T2D and IGT were significantly prevalent in WW and RW subjects relative to RR among all 797 subjects (P = .0138) and also in hypertriglyceridemic subjects (P = .0015). In multiple logistic regression models for the existence of T2D and IGT in hypertriglyceridemic subjects, the odds ratio for heterozygote RW and homozygote WW genotypes to wild-type RR was 2.406 (P = .0017) after controlling the risk factors of age, gender, and body mass index as covariates.

CONCLUSIONS

The frequency of ANGPTL8 R59W is significantly higher in Japanese subjects than in other ethnic groups. The rates of T2D and IGT were greater in subjects with the R59W variant. These findings indicate that ANGPTL8 is a participant in diabetes and a potential therapeutic target for T2D prevention, especially in East Asians.

Insulinoma Presenting with Reactive Hypoglycemia: Evaluating the Effect of Tumor Resection via Continuous Glucose Monitoring

A 71-year-old woman previously diagnosed with reactive hypoglycemia was transferred to our emergency unit because of loss of consciousness. Her plasma glucose level was 27 mg/dL, and continuous glucose monitoring (CGM) revealed postprandial asymptomatic hypoglycemia. A hypervascular tumor was identified via computed tomography in the distal pancreas, and the diagnosis of insulinoma was confirmed using the selective arterial calcium stimulation test. Although no episodes of hypoglycemia were observed during CGM after resection, a pathological examination identified regional lymph node metastasis. It is important to consider insulinoma as a cause of postprandial hypoglycemia, and CGM is useful for evaluating treatment outcomes.

High risk of renal dysfunction in patients with fulminant type 1 diabetes

AIMS/INTRODUCTION

To compare the incidence rate of renal dysfunction between patients with fulminant type 1 diabetes and those with acute-onset type 1 diabetes.

MATERIALS AND METHODS

The present retrospective cohort study included patients with fulminant type 1 diabetes and acute-onset type 1 diabetes diagnosed during April 1993 to March 2016 at a national center in Japan. Glycated hemoglobin levels, incidence rates of renal dysfunction defined as an estimated glomerular filtration rate of <60 mL/min/1.73 m² and microalbuminuria were examined.

RESULTS

In total, 115 patients with type 1 diabetes (10 with fulminant type 1 diabetes and 105 with acute-onset type 1 diabetes) were included. The median glycated hemoglobin levels were significantly lower in patients with fulminant type 1 diabetes than in those with acute-onset type 1 diabetes 0, 3, 6 and 9 years after diabetes onset (6.5 vs 12.7%, 6.5 vs 7.9%, 6.7 vs 8.2%, 7.5 vs 8.5%, respectively). Kaplan-Meier analysis showed a significantly higher incidence rate of renal dysfunction in patients with fulminant type 1 diabetes than in those with acute-onset type 1 diabetes (hazard ratio 1.72, 95% confidence interval 1.01-2.97, P = 0.037). The incidence rate of microalbuminuria did not significantly differ between the groups (hazard ratio 0.97, 95% confidence interval 0.34-2.77, P = 0.95). Sensitivity analysis using age- and sex-matched patients with fulminant type 1 diabetes and acute-onset type 1 diabetes yielded similar results.

CONCLUSIONS

The risk of developing renal dysfunction is higher in patients with fulminant type 1 diabetes than in those with acute-onset type 1 diabetes, despite better glycemic control.

Adult-onset type 1 diabetes patients display decreased IGRP-specific Tr1 cells in blood

The breakdown of immune tolerance against islet antigens causes type 1 diabetes (T1D). The antigens associated with adult-onset T1D (AT1D) remain largely undefined. It is possible that AT1D patients display a unique type of CD4(+) T cells specific for a certain islet antigen. Here we analyzed the cytokine production profiles of CD4(+) helper T (Th) cells that are specific for three islet antigens; GAD65, preproinsulin, and IGRP in patients with AT1D, juvenile-onset T1D (JT1D), and age-, gender- and human leukocyte antigen (HLA)-matched control adults. While IGRP-specific Th cells in AT1D patients were dominantly Th1 cells, IGRP-specific Th cells in control adults and JT1D patients were dominantly Th2 and T regulatory type 1 (Tr1) cells. Notably, the frequency of IGRP-specific Tr1 cells was significantly lower in AT1D patients than in control adults and JT1D patients. In conclusion, our study suggests that IGRP-specific Th cells play a unique pathogenic role in AT1D.

An effective method to release human islets from surrounding acinar cells with agitation in high osmolality solution

INTRODUCTION

Islet purification is mainly performed by the density gradient method. However, purification of the embedded islets that are surrounded by exocrine tissue should be difficult, because their density is similar to exocrine tissue. In this study, we performed chart review to assess the relationship between the ratio of embedded islets and efficacy of purification. Then, we tested several conditions of a new method to free the islets from surrounded exocrine tissues using high osmolality solution with gentle agitation.

MATERIALS AND METHODS

First, we performed chart review of our human islet isolation. Second, embedded islet-enriched human islet fractions (embedded islets >50%) were suspended in University of Wisconsin (UW) solution (UW group, 320 mOsm/kg/H(2)0) or osmolality-adjusted UW solution (400, 500, and 600 mOsm/kg/H(2)0; 400 group, 500 group, and 600 group, respectively). Each tube was gently shaken at 4°C. The tissue samples were taken before shaking and after 15, 30, and 60 minutes. Islet yield, percentage of embedded islets, and viabilities were assessed.

RESULTS

The chart review revealed that high ratio of embedded islets deteriorated the efficacy of islet purification. The islet yield in all groups except for the 600 group did not change at 15 minutes, but it decreased in all groups at 60 minutes. The average percentage of embedded islets before shaking was 62.6%. Although percentage of embedded islets were decreasing in all groups, it was < 20% at 15 minutes in the 500 and 600 groups whereas it was >44% in the UW group, which indicated that higher osmolality would have a greater effect. Viability was >95% in all groups at 30 minutes.

CONCLUSIONS

The embedded islets deteriorated the efficacy of islet purification. Gentle agitation of embedded islets in high osmolality (500 mOsm/kg/H(2)O, 15 minutes) could release islets from surrounded exocrine tissue.

Usefulness of the secretory unit of islet transplant objects (SUITO) index for evaluation of clinical autologous islet transplantation

BACKGROUND

Assessing the engrafted islet mass is important in evaluating the efficacy of islet transplantation. We previously demonstrated that the average secretory unit of islet transplant objects (SUITO) index within 1 month of allogeneic islet transplantation was an excellent predictor of insulin independence. However, the usefulness of the SUITO index for evaluating autologous islet transplantation has not been explored. The purpose of the present study was to assess the relationship between the SUITO index and clinical outcomes after total pancreatectomy followed by autologous islet transplantation.

METHODS

We performed 27 total pancreatectomies followed by autologous islet transplantation from October 2006 to January 2011. Cases were divided into an insulin-independent group (IIG; n = 12) and an insulin-dependent group (lDG; n = 15). The SUITO index was calculated by the formula [fasting C-peptide (ng/mL)/fasting glucose (mg/dL) -63] × 1,500. The average SUITO index within the first month of transplantation except for days 0, 1, and 2, maximum SUITO index, and most recent SUITO index were calculated in each case, and values were compared between the IIG and the IDG.

RESULTS

The average SUITO index within 1 month was significantly higher in the IIG than in the IDG (24.6 ± 3.4 vs 14.9 ± 2.0, respectively; P < .02). The maximum SUITO indices were 45.7 ± 7.7 in the IIG and 30.1 ± 8.1 in the IDG (not significant), and the recent SUITO indices were 36.9 ± 6.7 in the IIG and 22.8 ± 6.1 in the IDG (not significant).

CONCLUSIONS

The average SUITO index within 1 month was an excellent predictor of insulin independence after total pancreatectomy followed by autologous islet transplantation.

Insulin administration may trigger type 1 diabetes in Japanese type 2 diabetes patients with type 1 diabetes high-risk HLA class II and the insulin gene VNTR genotype

CONTEXT

Insulin administration causes various types of immune responses to insulin. We previously reported three cases of type 1 diabetes mellitus (T1DM) triggered by insulin administration in Japanese type 2 diabetes mellitus patients.

OBJECTIVE

The objective of this study was to collect information and characterize insulin-triggered T1DM immunologically and genetically.

METHODS

Data for six patients (four men and two women) with insulin-triggered T1DM aged 59.5 ± 12.8 years were collected. Serum or urinary C-peptides, islet-related autoantibodies, insulin antibody, human leukocyte antigen, or the insulin gene variable number of tandem repeat genotype were analyzed. Th1- or Th2-associated responses were evaluated using an Enzyme-Linked ImmunoSpot assay.

RESULTS

None of the subjects had received insulin therapy or had an autoantibody to the 65-kDa isoform of glutamic acid decarboxylase before insulin administration. After insulin administration blood glucose control deteriorated acutely without any apparent cause, whereas C-peptide levels rapidly decreased to insulin-deficient levels. The mean duration of insulin administration to the development of T1DM was 7.7 ± 6.1 months. Islet-related autoantibodies became positive, whereas insulin allergy or a high titer of insulin antibody was observed in several cases. All had T1DM high-risk human leukocyte antigen class II (IDDM1) and the insulin gene variable number of tandem repeats genotype (IDDM2). GAD-reactive and insulin peptide-reactive Th1 cells, but not Th2 cells, were identified in two of four cases.

CONCLUSIONS

The findings suggest that insulin administration may have triggered TIDM in patients with type 2 diabetes mellitus. IDDM1 and IDDM 2 as well as autoreactive T cells may contribute to the development of T1DM. Developing insulin-triggered T1DM if a patient's blood glucose control acutely deteriorates after insulin administration should be carefully considered.

A new method for generating insulin-secreting cells from human pancreatic epithelial cells after islet isolation transformed by NeuroD1

The generation of insulin-secreting cells from nonendocrine pancreatic epithelial cells (NEPEC) has been demonstrated for potential clinical use in the treatment of diabetes. However, previous methods either had limited efficacy or required viral vectors, which hinder clinical application. In this study, we aimed to establish an efficient method of insulin-secreting cell generation from NEPEC without viral vectors. We used nonislet fractions from both research-grade human pancreata from brain-dead donors and clinical pancreata after total pancreatectomy with autologous islet transplantation to treat chronic pancreatitis. It is of note that a few islets could be mingled in the nonislet fractions, but their influence could be limited. The NeuroD1 gene was induced into NEPEC using an effective triple lipofection method without viral vectors to generate insulin-secreting cells. The differentiation was promoted by adding a growth factor cocktail into the culture medium. Using the research-grade human pancreata, the effective method showed high efficacy in the differentiation of NEPEC into insulin-positive cells that secreted insulin in response to a glucose challenge and improved diabetes after being transplanted into diabetic athymic mice. Using the clinical pancreata, similar efficacy was obtained, even though those pancreata suffered chronic pancreatitis. In conclusion, our effective differentiation protocol with triple lipofection method enabled us to achieve very efficient insulin-secreting cell generation from human NEPEC without viral vectors. This method offers the potential for supplemental insulin-secreting cell transplantation for both allogeneic and autologous islet transplantation.

Improving allogeneic islet transplantation by suppressing Th17 and enhancing Treg with histone deacetylase inhibitors

Islet transplantation is a new treatment for achieving insulin independence for patients with severe diabetes. However, major drawbacks of this treatment are the long graft survival, the necessity for immunosuppressive drugs, and the efficacy of transplantation. Donor-specific transfusion (DST) has been shown to reduce rejection after organ transplantation, potentially through enhanced regulatory T-cell (Treg) activity. However, recent findings have shown that activated Treg can be converted into Th17 cells. We focused on histone deacetylase inhibitors (HDACi) because it was reported that inhibition of HDAC activity prevented Treg differentiation into IL17-producing cells. We therefore sought to enhance Treg while suppressing Th17 cells using DST with HDACi to prolong graft survival. To stimulate Treg by DST, we used donor splenocytes. In DST with HDACi group, Foxp3 mRNA expression and Treg population increased in the thymus and spleen, whereas Th17 population decreased. qPCR analysis of lymphocyte mRNA indicated that Foxp3, IL-10, and TGF-b expression increased. However, interleukin 17a, Stat3 (Th17), and IFN-g expression decreased in DST + HDACi group, relative to DST alone. Moreover, DST treated with HDACi prolonged graft survival relative to controls in mice islet transplantation. DST with HDACi may therefore have utility in islet transplantation.

Analysis of pancreatic endocrine function in patients with IgG4-related diseases, in whom autoimmune pancreatitis was ruled out by diagnostic imaging

IgG4-related disease (IgG4RD) is a newly recognized systemic disease characterized by the elevation of serum IgG4 levels and abundant IgG4-positive plasma cell infiltration into the involved organs. Few data exist regarding the relationship between diabetes or glucose intolerance and IgG4RD in the absence of obvious type 1 autoimmune pancreatitis (AIP). Therefore, we are characterizing pancreatic endocrine function in IgG4RD patients with no signs of type 1 AIP. 28 patients (12 men, mean age 62.1 years old) were diagnosed as having IgG4RD from serum IgG4 levels, histopathology and images. Diagnostic imaging ruled out obvious type 1AIP. We used 75g oral glucose tolerance tests (OGTT) and arginine tolerance tests (ATT) to evaluate pancreatic endocrine function. Patients' serum IgG4 and HbA1c levels were 603±437 mg/dL and 6.6±1.0%, respectively. The results of OGTT on 23 patients showed that 12 patients had diabetes, 4 had impaired glucose tolerance, and 7 had normal glucose tolerance. Interestingly, insulin secretion was preserved in most of the patients, even in diabetic patients, on OGTT and ATT. Glucagon hyperreactivity was observed in 10 of the 19 patients who underwent ATT. Twenty-three patients were treated for IgG4RD with glucocorticoids. Their HbA1c levels were significantly elevated during the first six months of treatment, but improved after twelve months in parallel with glucocorticoid therapy. These results demonstrate the high frequency of pancreatic endocrine dysfunction in IgG4RD even when there is no indication of AIP, thus revealing that pancreatic endocrine dysfunction frequently occurs in IgG4RD without obvious type 1 AIP.

Low temperature condition prevents hypoxia-induced islet cell damage and HMGB1 release in a mouse model

One of the major issues in clinical islet transplantation is the poor efficacy of islet isolation. During pancreas preservation and islet isolation, islets suffer from hypoxia as islets are highly sensitive to hypoxic conditions.Cold preservation has been applied to minimize hypoxia-induced cell damage during organ preservation.However, the studies related to hypoxia-induced islet cell damage during islet isolation are limited. Recently,we demonstrated that mouse islets contain high levels of high-mobility group box 1 protein (HMGB1), and during proinflammatory cytokine-induced damage, islets release HMGB1 outside the cell. The released HMGB1 is involved in the initial events of early islet loss. In the present study, we hypothesize that low temperature conditions could prevent both hypoxia induced islet cell damage and HMGB1 release from islets in a mouse model. Isolated mouse islets underwent normoxic condition (95% air and 5% CO(2)) at 37°C or hypoxic conditions (1% O(2), 5% CO(2), and 94% N(2)) at 37°C (hypoxia-37°C islets), 22°C (hypoxia-22°C islets), or 4°C (hypoxia-4°C islets) for 12 h. In vitro and in vivo viability and functionality tests were performed. HMGB1, IL-6, G-CSF, KC, RANTES, MCP-1, and MIP-1α levels in the medium were measured. Low temperature conditions substantially reduced hypoxia-induced necrosis (p < 0.05) and apoptosis (p < 0.05). In addition, low temperature islet culture significantly increased the insulin secretion from islets by high glucose stimulation (p < 0.05). All of the recipient mice reversed diabetes after receiving the hypoxia-4°C islets but not after receipt of hypoxia-37°C or 22°C islets. The amounts of released HMGB1, IL-6, G-CSF, KC, RANTES, MCP-1, and MIP-1α were significantly reduced in the hypoxia-4°C islets compared to those of the hypoxia-37°C islets (p < 0.05). In conclusion, low temperature conditions could prevent hypoxia-induced islet cell damage, inflammatory reactions in islets, and HMGB1 release and expression. Low temperature conditions should improve the efficacy of isolated islets.

Correlation of released HMGB1 levels with the degree of islet damage in mice and humans and with the outcomes of islet transplantation in mice

Establishing reliable islet potency assay is a critical and unmet issue for clinical islet transplantation. Recently, we reported that islets contained high levels of high mobility group box 1 (HMGB1) and damaged islets released HMGB1 in a mouse model. In this study, we hypothesized that the amount of released HMGB1 could reflect the degree of islet damage, and could predict the outcome of islet transplantation. Four groups of damaged mouse islets and three groups of damaged human islets were generated by hypoxic conditions. These islets were assessed by in vivo (transplantation) and in vitro (released HMGB1 levels, released C-peptide levels, PI staining, TUNEL staining, ATP/DNA, and glucose-stimulated insulin release test) assays. In addition, the ability of each assay to distinguish between noncured (n = 13) and cured (n = 7) mice was assessed. The curative rates of STZ-diabetic mice after receiving control, hypoxia-3h, hypoxia-6h, and hypoxia-24h mouse islets were 100%, 40%, 0%, and 0%, respectively. Only amounts of released HMGB1 and ratio of PI staining significant increased according to the degree of damages in both human and mouse islets. In terms of predictability of curing diabetic mice, amounts of released HMGB1 showed the best sensitivity (100%), specificity (100%), positive (100%), and negative predictive values (100%) among all the assays. The amount of released HMGB1 reflected the degree of islet damage and correlated with the outcome of islet transplantation in mice. Hence, released HMGB1 levels from islets should be a useful marker to evaluate the potency of isolated islets.

Safety and tolerability of the T-cell depletion protocol coupled with anakinra and etanercept for clinical islet cell transplantation

BACKGROUND

Islet cell transplantation (ICT) is a promising approach to cure patients with type 1 diabetes. We have implemented a new immunosuppression protocol with antithymoglobulin plus anti-inflammatory agents of anakinra and eternacept for induction and tacrolimus plus mycophenolate mofetil for maintenance [T-cell depletion with anti-inflammatory (TCD-AI) protocol], resulting in successful single-donor ICT.

METHODS

Eight islet recipients with type 1 diabetes reported adverse events (AEs) monthly. AEs were compared between three groups: first infusion with the TCD-AI protocol (TCD-AI-1st) and first and second infusion with the Edmonton-type protocol (Edmonton-1st and Edmonton-2nd).

RESULTS

The incidence of symptomatic AEs within the initial three months in the TCD-AI-1st group was less than in the Edmonton-1st and Edmonton-2nd groups, with a marginally significant difference (mean ± SE: 5.5 ± 0.3, 7.5 ± 0.5, and 8.3 ± 1.3, respectively; p = 0.07). A significant reduction in liver enzyme elevation after ICT was found in the TCD-AI-1st group compared with the Edmonton-1st and Edmonton-2nd groups (p < 0.05). Because of AEs, all patients in the Edmonton protocol eventually converted to the TCD-AI protocol, whereas all patients tolerated the TCD-AI protocol.

CONCLUSIONS

TCD-AI protocol can be tolerated for successful ICT, although this study includes small cohort, and large population trial should be taken.

ZnT8-Specific CD4+ T cells display distinct cytokine expression profiles between type 1 diabetes patients and healthy adults

Determination of antigen-specific T cell repertoires in human blood has been a challenge. Here, we show a novel integrated approach that permits determination of multiple parameters of antigen-specific T cell repertoires. The approach consists of two assays: the Direct assay and the Cytokine-driven assay. Briefly, human PBMCs are first stimulated with overlapping peptides encoding a given antigen for 48 hours to measure cytokine secretion (Direct assay). Peptide-reactive T cells are further expanded by IL-2 for 5 days; and after overnight starvation, expanded cells are stimulated with the same peptides from the initial culture to analyze cytokine secretion (Cytokine-driven assay). We first applied this integrated approach to determine the type of islet-antigen-specific T cells in healthy adults. Out of ten donors, the Direct assay identified GAD65-specific CD4⁺ T cells in three adults and zinc transporter 8 (ZnT8)-specific CD4⁺ T cells in five adults. The intracytoplasmic cytokine staining assay showed that these islet-antigen-specific CD4⁺ T cells belonged to the CD45RO⁺ memory compartment. The Cytokine-driven assay further revealed that islet-antigen-specific CD4⁺ T cells in healthy adults were capable of secreting various types of cytokines including type 1 and type 2 cytokines as well as IL-10. We next applied our integrated assay to determine whether the type of ZnT8-specific CD4⁺ T cells is different between Type 1 diabetes patients and age/gender/HLA-matched healthy adults. We found that ZnT8-specific CD4⁺ T cells were skewed towards Th1 cells in T1D patients, while Th2 and IL-10-producing cells were prevalent in healthy adults. In conclusion, the Direct assay and the Cytokine-driven assay complement each other, and the combination of the two assays provides information of antigen-specific T cell repertoires on the breadth, type, and avidity. This strategy is applicable to determine the differences in the quality of antigen-specific T cells between health and disease.

Elevation of high-mobility group box 1 after clinical autologous islet transplantation and its inverse correlation with outcomes

A major problem after clinical autologous islet transplantation (AIT) is the difficulty in achieving insulin independence. To follow up on our demonstration in a murine model that high-mobility group box 1 (HMGB1) was released from islets and involved in early loss of transplanted islets, we tested the role of HMGB1 in clinical AIT. Serum HMGB1 levels from 15 AIT patients were significantly elevated during islet infusion (7.6 ± 1.2 ng/ml) and 24 h after infusion (8.0 ± 1.4 ng/ml) compared to admission levels (2.4 ± 0.6 ng/ml). The first elevation of HMGB1 was associated with islet damage, but the later elevation was not. The change in the HMGB1 level from admission to first peak (ΔHMGB1) was significantly higher in the AIT group (8.1 ± 1.1 ng/ml) than in the pancreatectomy-only control (2.2 ± 0.5 ng/ml) (p < 0.05). Circulating serum levels of soluble receptor for advanced glycation end products (sRAGE) were also elevated during islet infusion. In vitro studies demonstrated that damaged human islets released HMGB1 but not sRAGE. In terms of outcomes, the insulin-free group showed significantly lower ΔHMGB1 (5.2 ± 0.6 ng/ml) and higher ΔsRAGE (2.3 ± 0.6 ng/ml) than the insulin-dependent group (10.6 ± 1.9 ng/ml and 0.7 ± 0.2 ng/ml, respectively). The ΔHMGB1 correlated with the number of white blood cell, IP-10, EGF, and eotaxin. In conclusion, serum HMGB1 was elevated in AIT and could be associated with inflammatory reactions that deteriorate islet engraftment. Therefore, anti-HMGB1 therapy might be a candidate for further improving the outcomes of clinical AIT.

Fresh islets are more effective for islet transplantation than cultured islets

For clinical islet transplantation, isolated islets deteriorate rapidly in culture, although culturing islets prior to transplantation provides flexibility for evaluation of isolated islets and pretreatment of patients. In the present study, we compared human fresh islets to cultured islets with in vitro and in vivo assays. After culture for 24, 48, and 72 h, islet yield significantly decreased from 2,000 to 1,738 ± 26 (13% loss), 1,525 ± 30 (24% loss), or 1,298 ± 18 IEQ (35% loss), respectively. The ATP contents were significantly higher in the 6-h cultured group (near fresh group) than in 48-h culture groups. The stimulation index was relatively higher in the 6-h cultured group than in 48-h cultured group. Human islets with or without culture were transplanted into diabetic nude mice. The attainability of posttransplantation normoglycemia was significantly higher in fresh group than in the culture groups. Intraperitoneal glucose tolerance testing (IPGTT) showed that the blood glucose levels of mice transplanted with fresh islets were significantly lower than with cultured islets at 30, 60, 90, and 120 min after injection. These data suggest that human islet transplantation without culture could avoid the deterioration of islets during culture and improve the outcome of islet transplantation. Based on these data, we have transplanted fresh islets without culture for our current clinical islet transplantation protocol.