title: Effect of sitagliptin on glycemic control and beta cell function in Japanese patients given basal-supported oral therapy for type 2 diabetes.
abstract: We evaluated the effect of sitagliptin on glycemic control, endogenous insulin secretion, and beta cell function in Japanese patients with type 2 diabetes mellitus (T2DM) receiving a combination of oral antidiabetics and basal insulin analog glargine (basal-supported oral therapy [BOT]). Twenty-one patients showing inadequate glycemic control with BOT were given dipeptidylpeptidase-4 inhibitor (DPP-4I) sitagliptin at 50 mg/day for 12 weeks. Clinical markers of glycemic control, HbA1c, glycated albumin (GA), and 1,5-anhydroglucitol (1,5-AG), were measured before and 4 and 12 weeks after the start of sitagliptin. A 2-hour morning meal test was performed upon enrollment and at 12 weeks, and plasma glucose (PG), serum C-peptide, and plasma intact proinsulin (PI) were measured. HbA1c, GA, and 1,5-AG at 4 and 12 weeks were significantly improved over enrollment levels. The area under the PG concentration curve (AUC-PG) during the meal test at 12 weeks was significantly reduced (from 350 ± 17 mg ･ hr/dL before sitagliptin treatment to 338 ± 21 mg ･ hr/dL [mean ± SE], P < 0.05,); the AUC-C-peptide was unchanged (from 3.4 ± 0.4 ng ･ hr/mL to 3.6 ± 0.5 ng ･ hr/mL). However, both fasting and 2-hour PI/C-peptide ratios at 12 weeks were significantly decreased (from 13.3 ± 2.3 to 11.1 ± 2.0 [P < 0 .05] and from 9.5 ± 1.6 to 5.3 ± 0.9 [P < 0.01], respectively). Adding sitagliptin to BOT in Japanese T2DM patients appears to improve glycemic control without increasing endogenous insulin secretion and to reduce fasting and 2-hour postprandial PI/C-peptide ratios.
authors.affiliation: Department of Internal Medicine, Division of Metabolism and Endocrinology, St. Marianna University School of Medicine, Kawasaki 216-8511, Japan.
authors.forename: Shiko
authors.initials: S
authors.lastname: Asai
authors.forename: Akio
authors.initials: A
authors.lastname: Ohta
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Kato
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Sada
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Nagai
authors.forename: Akihiko
authors.initials: A
authors.lastname: Kondo
authors.forename: Toshiyasu
authors.initials: T
authors.lastname: Sasaoka
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Tanaka
mesh_terms: D000284:Administration, Oral; D000368:Aged; D000465:Algorithms; D015415:Biomarkers / Q000097:blood; D002096:C-Peptide / Q000097:blood; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000188:drug therapy* / Q000208:ethnology / Q000503:physiopathology; D054873:Dipeptidyl-Peptidase IV Inhibitors / Q000008:administration & dosage / Q000627:therapeutic use*; D016903:Drug Monitoring; D004351:Drug Resistance; D004359:Drug Therapy, Combination; D005230:Fatty Acids, Nonesterified / Q000037:antagonists & inhibitors / Q000097:blood; D005260:Female; D006442:Glycated Hemoglobin / Q000032:analysis; D006801:Humans; D006943:Hyperglycemia / Q000517:prevention & control*; D007004:Hypoglycemic Agents / Q000008:administration & dosage / Q000627:therapeutic use; D000069036:Insulin Glargine; D049528:Insulin, Long-Acting / Q000008:administration & dosage / Q000627:therapeutic use; D050417:Insulin-Secreting Cells / Q000187:drug effects* / Q000378:metabolism; D007564:Japan; D008297:Male; D011384:Proinsulin / Q000097:blood / Q000378:metabolism*; D011719:Pyrazines / Q000008:administration & dosage / Q000627:therapeutic use*; D000068900:Sitagliptin Phosphate; D014230:Triazoles / Q000008:administration & dosage / Q000627:therapeutic use*
chemical_list: D015415:Biomarkers; D002096:C-Peptide; D054873:Dipeptidyl-Peptidase IV Inhibitors; D005230:Fatty Acids, Nonesterified; D006442:Glycated Hemoglobin; D007004:Hypoglycemic Agents; D000069036:Insulin Glargine; D049528:Insulin, Long-Acting; D011384:Proinsulin; D011719:Pyrazines; D000068900:Sitagliptin Phosphate; D014230:Triazoles; C517652:hemoglobin A1c protein, human