title: Pigment epithelium-derived factor increases in type 2 diabetes after treatment with metformin.
abstract: OBJECTIVE
  Pigment epithelium-derived factor (PEDF) has anti-angiogenic, immunomodulatory and anti-inflammatory properties. In addition to the significant role it plays in reducing diabetic complications, PEDF is now used in the treatment of certain cancers. It possibly plays a role in insulin resistance cases, too. However, whether metformin treatment has any significant effects on PEDF levels is not known. In this study, we investigated the regulation of PEDF in type 2 diabetes in relation to fat mass and insulin resistance before and after the use of metformin for treatment.
  
  
  METHODS
  Prospective cohort study.
  
  
  METHODS
  Thirty-six patients with newly diagnosed type 2 diabetes and 33 healthy individuals.
  
  
  METHODS
  Baseline weight, waist circumference (WC), fasting (FPG) and postprandial (PPPG) glucose, insulin, HbA1c, HOMA, PEDF and total/truncal fat mass were determined both in the diabetic and control subjects. Procedures were repeated in the diabetic group after a 6-month metformin treatment.
  
  
  RESULTS
  Baseline FPG, PPPG, HbA1c, HOMA, weight, WC and truncal fat mass were higher in patients with diabetes whereas PEDF levels were found to be comparable with the controls. We completed the study with 31 of the 36 patients with diabetes we had selected for the study. We observed a decrease in the weight, WC, FPG, PPPG, HOMA, total and truncal fat mass of the patients while there was a significant rise in the PEDF levels (P = 0·002) after the metformin treatment. On the other hand, no significant correlation was observed between the change in PEDF levels and the clinical and laboratory findings.
  
  
  CONCLUSIONS
  Our study is the first to identify a metformin-related increase in PEDF levels in diabetes. The increase observed in PEDF levels after the metformin treatment does not seem to be related to the changes in insulin resistance, fat mass or glycemic control. Hence, our results suggest that further investigation is necessary to determine the direct effects of metformin on PEDF gene and protein expression in vitro.
authors.affiliation: Department of Internal Medicine, Hacettepe University, Ankara, Turkey.
authors.forename: Safak
authors.initials: S
authors.lastname: Akın
authors.forename: Duygu Yazgan
authors.initials: DY
authors.lastname: Aksoy
authors.forename: Neşe
authors.initials: N
authors.lastname: Cınar
authors.forename: Kadriye
authors.initials: K
authors.lastname: Aydın
authors.forename: Ergun
authors.initials: E
authors.lastname: Karaağaoğlu
authors.forename: Macit
authors.initials: M
authors.lastname: Arıyürek
authors.forename: Neşe Ersöz
authors.initials: NE
authors.lastname: Gülçelik
authors.forename: Aydan
authors.initials: A
authors.lastname: Usman
authors.forename: Alper
authors.initials: A
authors.lastname: Gürlek
mesh_terms: D000328:Adult; D050218:Body Fat Distribution; D015331:Cohort Studies; D003924:Diabetes Mellitus, Type 2 / Q000097:blood* / Q000188:drug therapy*; D005136:Eye Proteins / Q000097:blood*; D005260:Female; D006442:Glycated Hemoglobin / Q000032:analysis; D006801:Humans; D007004:Hypoglycemic Agents / Q000627:therapeutic use*; D007333:Insulin Resistance; D008297:Male; D008687:Metformin / Q000627:therapeutic use*; D008875:Middle Aged; D009414:Nerve Growth Factors / Q000097:blood*; D011446:Prospective Studies; D015843:Serpins / Q000097:blood*; D055105:Waist Circumference; D000099174:Pigment Epithelium-Derived Factor
chemical_list: D005136:Eye Proteins; D006442:Glycated Hemoglobin; D007004:Hypoglycemic Agents; D008687:Metformin; D009414:Nerve Growth Factors; D015843:Serpins; D000099174:Pigment Epithelium-Derived Factor