title: Basal and stimulated calcitonin levels in patients with type 2 diabetes did not change during 1 year of Liraglutide treatment.
abstract: OBJECTIVE
  The administration of Liraglutide, a long-acting GLP-1 receptor (GLP-1R) agonist, is associated with C-cell adenomas and carcinomas in rats. In humans, GLP-1R is highly expressed in C-cells hyperplasia (CCH) and in medullary thyroid cancer (MTC), though no changes in basal serum calcitonin (bCT) levels were recorded in type 2 diabetic (T2DM) patients treated with Liraglutide. To diagnose the possible development of CCH during Liraglutide treatment, we evaluated CT levels stimulated by calcium test (sCT).
  
  
  METHODS
  bCT and sCT and metabolic and anthropometric parameters were evaluated in 26 T2DM patients at baseline and at 1, 3, 6 and 12 months of treatment.
  
  
  RESULTS
  In all patients, bCT remained within the normal range during the entire study period. In females and males, the higher sCT values were reached after 3 months and 1 month, respectively, with a progressive reduction at 6-12 months. The greater decrease of HbA1c values was reached at 3 months, while body weight and waist circumference decreased over the first 4 weeks of therapy. Lipase levels significantly increased, with a peak value at 1 month.
  
  
  CONCLUSIONS
  The chronic administration of Liraglutide did not lead to statistically significant variations in both bCT and sCT. Stimulated CT levels increased, though always below the normal range, during the first 1-3 months of treatment, and progressively decreased to baseline levels. This finding is consistent with the effects recorded at the glycometabolic level, and suggests the possible induction of a drug tolerance involving also the C cells and thus preventing CCH.
authors.affiliation: Endocrine Unit, Fondazione IRCCS Ca' Granda, Milan, Italy; Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy.
authors.forename: Maria Elena
authors.initials: ME
authors.lastname: Lunati
authors.affiliation: Endocrine Unit, Fondazione IRCCS Ca' Granda, Milan, Italy; Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy.
authors.forename: Valeria
authors.initials: V
authors.lastname: Grancini
authors.affiliation: Endocrine Unit, Fondazione IRCCS Ca' Granda, Milan, Italy; Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy.
authors.forename: Carla
authors.initials: C
authors.lastname: Colombo
authors.affiliation: Endocrine Unit, Fondazione IRCCS Ca' Granda, Milan, Italy.
authors.forename: Eva
authors.initials: E
authors.lastname: Palmieri
authors.affiliation: Endocrine Unit, Fondazione IRCCS Ca' Granda, Milan, Italy.
authors.forename: Veronica
authors.initials: V
authors.lastname: Resi
authors.affiliation: Endocrine Unit, Fondazione IRCCS Ca' Granda, Milan, Italy; Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy.
authors.forename: Michela
authors.initials: M
authors.lastname: Perrino
authors.affiliation: Endocrine Unit, Fondazione IRCCS Ca' Granda, Milan, Italy. Electronic address: emanuela_orsi@yahoo.it.
authors.forename: Emanuela
authors.initials: E
authors.lastname: Orsi
authors.affiliation: Endocrine Unit, Fondazione IRCCS Ca' Granda, Milan, Italy; Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy. Electronic address: laura.fugazzola@unimi.it.
authors.forename: Laura
authors.initials: L
authors.lastname: Fugazzola
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002116:Calcitonin / Q000097:blood*; D003924:Diabetes Mellitus, Type 2 / Q000188:drug therapy*; D005260:Female; D006442:Glycated Hemoglobin / Q000032:analysis; D006801:Humans; D007004:Hypoglycemic Agents / Q000494:pharmacology*; D000069450:Liraglutide / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D000097789:Glucagon-Like Peptide-1 Receptor Agonists
chemical_list: D002116:Calcitonin; D006442:Glycated Hemoglobin; D007004:Hypoglycemic Agents; D000069450:Liraglutide; D000097789:Glucagon-Like Peptide-1 Receptor Agonists; C517652:hemoglobin A1c protein, human
keywords: Calcitonin; Calcium; Liraglutide; Stimulation