title: Short-term treatment with metformin decreases serum leptin concentration without affecting body weight and body fat content in normal-weight healthy men.
abstract: A weight-reducing effect of metformin has been demonstrated in obese subjects with and without diabetes. The mechanisms of this action are unclear, which may be partly due to the fact that in obese and diabetic patients the substance's effects result from a complex interaction with the distinct endocrine and metabolic disturbances in these patients. To dissociate primary from secondary action of metformin, we examined effects of the substance in normal-weight healthy subjects. Fifteen normal-weight men were treated with metformin (850 mg twice daily) or placebo for a 15-day period in a double-blind, placebo-controlled, cross-over study. Anthropometric, psychologic, cardiovascular, endocrine, and metabolic parameters were assessed before and at the end of the treatment period. Metformin did not affect body weight (P =.838) and body fat mass (P =.916). Yet, serum leptin concentration was distinctly reduced after metformin (P <.001). Also, metformin reduced the concentration of plasma glucose (P =.011), serum insulin (P=.044), and serum insulin-like growth factor -1 (IGF-1) (P=.013), while it increased serum glucagon concentration (P <.001). There were no effects of metformin on feelings of hunger, blood pressure, heart rate, resting energy expenditure, the respiratory quotient, free fatty acids, beta-hydroxybutyrate, glycerol, triglycerides, cholesterol, and uric acid (all P >.1). Data indicate that metformin decreases the serum leptin concentration even without affecting body weight and body composition in normal-weight men.
authors.affiliation: Department of Internal Medicine I, University of Luebeck, Luebeck, Germany.
authors.forename: Bernd
authors.initials: B
authors.lastname: Fruehwald-Schultes
authors.forename: Kerstin M
authors.initials: KM
authors.lastname: Oltmanns
authors.forename: Barbara
authors.initials: B
authors.lastname: Toschek
authors.forename: Stefan
authors.initials: S
authors.lastname: Sopke
authors.forename: Werner
authors.initials: W
authors.lastname: Kern
authors.forename: Jan
authors.initials: J
authors.lastname: Born
authors.forename: Horst L
authors.initials: HL
authors.lastname: Fehm
authors.forename: Achim
authors.initials: A
authors.lastname: Peters
mesh_terms: D000273:Adipose Tissue / Q000033:anatomy & histology* / Q000187:drug effects; D000328:Adult; D001794:Blood Pressure / Q000187:drug effects; D001835:Body Weight / Q000187:drug effects; D002096:C-Peptide / Q000097:blood; D003920:Diabetes Mellitus / Q000188:drug therapy; D005934:Glucagon / Q000097:blood; D006801:Humans; D006854:Hydrocortisone / Q000652:urine; D007004:Hypoglycemic Agents / Q000494:pharmacology*; D007328:Insulin / Q000097:blood; D007333:Insulin Resistance; D018972:Insulin-Like Growth Factor Binding Protein 3 / Q000097:blood; D007334:Insulin-Like Growth Factor I / Q000378:metabolism; D020738:Leptin / Q000097:blood*; D008297:Male; D008687:Metformin / Q000494:pharmacology*; D009765:Obesity / Q000188:drug therapy; D012016:Reference Values
chemical_list: D002096:C-Peptide; D007004:Hypoglycemic Agents; D007328:Insulin; D018972:Insulin-Like Growth Factor Binding Protein 3; D020738:Leptin; D007334:Insulin-Like Growth Factor I; D005934:Glucagon; D008687:Metformin; D006854:Hydrocortisone