Kazuki Tajima

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We previously reported that combination therapy with an α-glucosidase inhibitor (αGI) and a dipeptidyl peptidase-4 (DPP-4) inhibitor increased active glucagon-like peptide-1 (GLP-1) levels and decreased total glucose-dependent insulinotropic polypeptide (GIP) levels, compared with monotherapy, in non-diabetic men. However, the peptide YY (PYY),(More)
The derangement of endoplasmic reticulum (ER) homeostasis triggers β-cell apoptosis, leading to diabetes. Glucokinase upregulates insulin receptor substrate 2 (IRS-2) expression in β-cells, but the role of glucokinase and IRS-2 in ER stress has been unclear. In this study, we investigated the impact of glucokinase activation by glucokinase activator (GKA)(More)
BACKGROUND Diabetes therapy that not only lowers glucose levels but also lengthens life spans is required. We previously demonstrated that DPP-4 inhibition ameliorated β cell apoptosis and adipose tissue inflammation in β cell-specific glucokinase haploinsufficient mice fed a diet containing a combination of sucrose and linoleic acid (SL). METHODS In this(More)
Chronic exposure to high glucose and fatty acid levels caused by dietary sugar and fat intake induces β cell apoptosis, leading to the exacerbation of type 2 diabetes. Oleic acid and linoleic acid are two major dietary fatty acids, but their effects in diabetes are unclear. We challenged β cell-specific glucokinase haploinsufficient (Gck(+/-)) mice with a(More)
Peroxisome proliferator-activated receptor (PPAR)-γ agonists are clinically used as anti-diabetes agents. Recent research has discovered that an anti-inflammatory effect of PPAR agonist may have the potential to treat autoimmune disease. In the present study, we investigated the anti-inflammatory effects of PPAR-γ agonist, pioglitazone, on murine model of(More)
The patient was a 26-year-old man who had undergone patch closure of a ventricular septal defect at 2 years of age. After this surgery, his condition was satisfactory until he visited our hospital for treatment of paroxysmal supraventricular tachycardia in November 2000. Echocardiography revealed moderate to severe aortic valve regurgitation and dilatation(More)
PURPOSE Various immune mediators are hypothesized to have important roles in the pathogenesis of vitreoretinal B-cell lymphoma, although the exact mechanisms remain unclear. We determined the immune mediator profile in the vitreous of eyes with vitreoretinal B-cell lymphoma. METHODS We studied 28 eyes (23 patients) with vitreoretinal B-cell lymphoma, and(More)
The glucagon-like peptide-1 receptor agonist liraglutide is used to treat diabetes. A hallmark of liraglutide is the glucose-dependent facilitation of insulin secretion from pancreatic β-cells. In β-cells, the glycolytic enzyme glucokinase plays a pivotal role as a glucose sensor. However, the role of glucokinase in the glucose-dependent action of(More)
(Pro)renin receptor ((P)RR), a receptor for renin and prorenin, is implicated in the pathophysiology of diabetes mellitus, hypertension and their complications. Soluble (P)RR (s(P)RR) is composed of extracellular domain of (P)RR and thus exists in blood. We have reported that plasma concentrations of s(P)RR were elevated in male patients with obstructive(More)
Decreased β-cell mass is a hallmark of type 2 diabetes, and therapeutic approaches to increase the pancreatic β-cell mass have been expected. In recent years, gastrointestinal incretin peptides have been shown to exert a cell-proliferative effect in pancreatic β-cells. Trefoil factor 2 (TFF2), which is predominantly expressed in the surface epithelium of(More)