title: Teneligliptin, a Dipeptidyl Peptidase-4 Inhibitor, Improves Early-Phase Insulin Secretion in Drug-Naïve Patients with Type 2 Diabetes.
abstract: BACKGROUND
  It remains unknown whether dipeptidyl peptidase-4 (DPP-4) inhibitors improve early-phase insulin secretion in Japanese patients with type 2 diabetes (T2D), a disease characterized by impaired insulin secretion. We investigated the changes in insulin secretion before and after treatment with the DPP-4 inhibitor teneligliptin in patients with T2D with a low insulinogenic index (IGI) determined by the oral glucose tolerance test (OGTT).
  
  
  METHODS
  An open-label, prospective clinical study was conducted. Thirteen drug-naïve patients (mean age 55.5 ± 3.9 years) with T2D underwent OGTT before and after teneligliptin 20 mg/day monotherapy. Plasma levels of glucose (PG), insulin, and C-peptide were measured at 0, 30, 60, 90, and 120 min after glucose loading in the OGTT. Homeostasis model assessment (HOMA)-β, IGI, and the total or incremental area under the curve (AUC) for PG and insulin were measured. AUC120min for the secretory units of islets in transplantation (SUIT) index was also measured.
  
  
  RESULTS
  HbA1c significantly decreased from 8.3 ± 0.4% at baseline to 6.3 ± 0.2% after 12 weeks of teneligliptin treatment (p < 0.05). Incremental AUC120min PG also significantly decreased, and β-cell function assessed by IGI30min, AUC120min insulin, and the AUC120min SUIT index significantly increased (0.16 ± 0.05 vs. 0.28 ± 0.06, 2692 ± 333 µU·2h/mL vs. 3537 ± 361 µU·2h/mL, and 4261 ± 442 vs. 8290 ± 1147, respectively; all p < 0.05). HOMA-β was unchanged. The reduction in incremental AUC120min PG was significantly associated with the augmentation of IGI30min and the AUC120min SUIT index. No severe adverse events were observed.
  
  
  CONCLUSIONS
  Twelve weeks of teneligliptin treatment improved IGI30min, AUC120min, and the SUIT index in drug-naïve Japanese patients with T2D.
authors.affiliation: Division of Diabetes, Metabolism, and Endocrinology, Department of Medicine, Showa University School of Medicine, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo, 142-8666, Japan, rikarikaakaoka@yahoo.co.jp.
authors.forename: Rika
authors.initials: R
authors.lastname: Ito
authors.forename: Tomoyasu
authors.initials: T
authors.lastname: Fukui
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Hayashi
authors.forename: Anna
authors.initials: A
authors.lastname: Osamura
authors.forename: Makoto
authors.initials: M
authors.lastname: Ohara
authors.forename: Noriko
authors.initials: N
authors.lastname: Hara
authors.forename: Akiko
authors.initials: A
authors.lastname: Higuchi
authors.forename: Takeshi
authors.initials: T
authors.lastname: Yamamoto
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Hirano
mesh_terms: D000328:Adult; D000368:Aged; D001786:Blood Glucose / Q000187:drug effects; D002096:C-Peptide / Q000097:blood; D003924:Diabetes Mellitus, Type 2 / Q000188:drug therapy* / Q000378:metabolism*; D054873:Dipeptidyl-Peptidase IV Inhibitors / Q000494:pharmacology / Q000627:therapeutic use*; D005260:Female; D005951:Glucose Tolerance Test; D006801:Humans; D007328:Insulin / Q000378:metabolism*; D000078790:Insulin Secretion; D050417:Insulin-Secreting Cells / Q000187:drug effects; D008297:Male; D008875:Middle Aged; D011720:Pyrazoles / Q000494:pharmacology* / Q000627:therapeutic use*; D053778:Thiazolidines / Q000494:pharmacology* / Q000627:therapeutic use*; D055815:Young Adult
chemical_list: C579035:3-(4-(4-(3-methyl-1-phenyl-1H-pyrazol-5-yl)piperazin-1-yl)pyrrolidin-2-ylcarbonyl)thiazolidine; D001786:Blood Glucose; D002096:C-Peptide; D054873:Dipeptidyl-Peptidase IV Inhibitors; D007328:Insulin; D011720:Pyrazoles; D053778:Thiazolidines