Publications by authors named "Iichiro Shimomura"

The significance of glucagon in the pathophysiology of diabetes mellitus is widely recognized, but the mechanisms underlying dysregulated glucagon secretion are still unclear. Here, we explored the molecular mechanisms of glucagon dysregulation, using an in vitro model. Hamster-derived glucagon-secreting InR1G cells were exposed to high glucose (25 mM) levels for 12 h before analyzing glucagon secretion and the activity of components involved in insulin signaling.

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Context: Fulminant type 1 diabetes mellitus (T1DM) is thought to be partly caused by virus infection.

Objective: This study investigated the mechanism of β cell destruction in fulminant T1DM after drug-induced hypersensitivity syndrome (DIHS).

Methods: We determined the localization of human cytomegalovirus (HCMV), human herpesvirus 6 (HHV-6), and Epstein-Barr virus (EBV) and the expression of interferon regulatory factor 3 (IRF3) and viral receptors of Z-DNA binding protein 1 (ZBP1) and retinoic acid-inducible gene I (RIG-I), together with inflammatory cells, by immunohistochemistry of the autopsy pancreas of a patient with fulminant T1DM with DIHS and in seven subjects with normal glucose tolerance who underwent pancreatectomy.

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Adiponectin, an adipocyte-derived circulating protein, accumulates in the heart, vascular endothelium, and skeletal muscles through an interaction with T-cadherin (T-cad), a unique glycosylphosphatidylinositol-anchored cadherin. Recent studies have suggested that this interaction is essential for adiponectin-mediated cardiovascular protection. However, the precise protein-protein interaction between adiponectin and T-cad remains poorly characterized.

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Objective The current study investigated whether or not patients taking multiple daily oral medications for lifestyle-related chronic diseases would have positive perspectives on changing one of their medications to a once-weekly one. Methods A total of 1,071 Japanese outpatients participated in the current study. We performed a questionnaire-based survey and compared the current satisfaction with the ongoing daily oral treatment (current daily-only treatment) and an expected satisfaction with an imaginary oral treatment changing one of their daily oral medications to a once-weekly oral medication (imaginary daily-and-weekly treatment).

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Primary aldosteronism (PA) is caused by excess secretion of aldosterone and is an independent risk factor for cardio-cerebro-vascular (CCV) events. The goal of treatment of PA should include prevention of CCV events. A definitive diagnosis of PA is established by confirmatory tests [saline infusion test (SIT), furosemide upright test (FUT) and captopril challenge test (CCT)].

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Figure 1 shows differences in treatment-induced delta change in carotid IMT relative to baseline, according to various pre-defined risk factors for atherosclerosis. These data suggest that treatment with DPP-4 inhibitors seem to prevent the progression of carotid atherosclerosis regardless of disease burden.

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The effect of dipeptidyl peptidase-4 (DPP-4) inhibitors on the regression of carotid IMT remains largely unknown. The present study aimed to clarify whether sitagliptin, DPP-4 inhibitor, could regress carotid intima-media thickness (IMT) in insulin-treated patients with type 2 diabetes mellitus (T2DM). .

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This study aimed to evaluate various metabolic parameters in patients with spinal and bulbar muscular atrophy (SBMA), to investigate the association between those indices and disease severity, and to explore the underlying molecular pathogenesis. We compared the degree of obesity, metabolic parameters, and blood pressure in 55 genetically confirmed SBMA patients against those in 483 age- and sex-matched healthy control. In SBMA patients, we investigated the correlation between these factors and motor functional indices.

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Among the therapeutic avenues being explored for replacement of the functional islet β-cell mass lost in type 1 diabetes (T1D), reprogramming of adult cell types into new β-cells has been actively pursued. Notably, mouse islet α-cells will transdifferentiate into β-cells under conditions of near β-cell loss, a condition similar to T1D. Moreover, human islet α-cells also appear to poised for reprogramming into insulin-positive cells.

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The physiological function of DPP-4 in proteolytic inactivation of incretins has been well established, however, there is limited information on the expression and the significance of DPP-4 in white adipose tissue with regard to obesity. The objective of the work was to reveal the expression and regulation of DPP-4 in adipocytes and compare the expression and activity of DPP-4 in white adipose tissue and several other organs such as the liver, muscle and kidney. We also investigated the gene expression levels of DPP-4 substrate chemokines, and their receptors in white adipose tissue.

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Aims/introduction: It is suggested that a positive psychosocial condition has a good effect on health and glycemic control. However, there has been no research to evaluate the association between positive psychosocial factors and diabetic nephropathy (DN). The aim of the present study was to evaluate the association between psychosocial factors and DN in patients with type 2 diabetes.

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Sleep pattern has been shown to be associated with type 2 diabetes mellitus. Here, we investigated the difference in bedtime, waking time and estimated sleep duration in type 2 diabetes mellitus patients with or without visceral fat accumulation, using a questionnaire on sleep patterns. The study participants were 59 Japanese type 2 diabetes mellitus patients (men/women 34/25, age 64.

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Background: Previous studies showed higher risk of cardiovascular and cerebrovascular (CCV) events in primary aldosteronism compared with essential hypertension, but the patients of these studies were limited to primary aldosteronism patients with high plasma aldosterone concentration (PAC). The introduction of the aldosterone-renin ratio as the screening test for primary aldosteronism led to the recognition of primary aldosteronism patients with normal PAC (nPA). However, there is no information on the risk of primary aldosteronism including nPA.

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Obesity is closely associated with various metabolic disorders. However, little is known about abnormalities in the metabolic change of obese adipose tissue. Here we use static metabolic analysis and metabolic turnover analysis to assess metabolic dynamics in obese mice.

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Aims: Adiponectin, an adipocyte-specific secretory protein, abundantly exists in the blood stream while its concentration paradoxically decreases in obesity. Hypoadiponectinemia is one of risks of cardiovascular diseases. However, impact of serum adiponectin concentration on acute ischemic myocardial damages has not been fully clarified.

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Introduction: The aim of this study was to determine the efficacy of insulin degludec (IDeg) relative to insulin glargine (IGlar) or insulin detemir (IDet) in glycemic control, as evaluated by continuous glucose monitoring (CGM) in insulin-deficient patients with type 1 diabetes.

Methods: We studied 28 outpatients treated with IGlar or IDet (IGlar/IDet). Basal insulin was switched to IDeg when glycemic control was considered unstable, as judged by the dawn phenomenon or nocturnal hypoglycemia.

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The effect of hypoglycemia on the progression of atherosclerosis in patients with type 2 diabetes mellitus (T2DM) remains largely unknown. This is a post hoc analysis of a randomized trial to investigate the relationship between hypoglycemic episodes and changes in carotid intima-media thickness (IMT). Among 274 study subjects, 104 patients experienced hypoglycemic episodes.

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Adiponectin, an adipocyte-derived protein abundant in the circulation, is thought to be protective against atherosclerosis. However, it is not fully understood how the association of adiponectin with vascular cells and its antiatherogenic effect are connected. In this study, T-cadherin was essential for accumulation of adiponectin in the neointima and atherosclerotic plaque lesions, and the adiponectin-T-cadherin association protected against vascular injury.

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Pdx1, a β-cell-specific transcription factor, has been shown to play a crucial role in maintaining β-cell function through transactivation of β-cell-related genes. In addition, it has been reported that the expression levels of Pdx1 are compromised under diabetic conditions in human and rodent models. We therefore aimed to clarify the possible beneficial role of Pdx1 against β-cell failure and generated the transgenic mouse that expressed Pdx1 conditionally and specifically in β cells (βPdx1) and crossed these mice with Ins2 diabetic mice.

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Background: Visceral fat plays a central role in the development of metabolic syndrome and atherosclerotic cardiovascular diseases. The association of visceral fat accumulation with cardio-metabolic diseases has been reported, but the impact of visceral fat on the gene expression profile in peripheral blood cells remains to be determined. The aim of this study was to determine the effects of visceral fat area (VFA) and subcutaneous fat area (SFA) on the gene expression profile in peripheral blood cells of obese subjects.

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Aim: Accumulation level of fluorescent advanced glycation end products (AGEs) in the skin can be measured non-invasively as skin autofluorescence (skin AF) by autofluorescence reader. The aim of this study was to assess possible associations between skin AF and diabetic complications, especially early-stage atherosclerosis, in Japanese type 1 diabetic patients.

Methods: Skin AF was measured by AGE reader® in 105 Japanese type 1 diabetic patients (34 men and 71 women, aged 37.

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