title: Cross-talk between body iron stores and diabetes: iron stores are associated with activity and microsatellite polymorphism of the heme oxygenase and type 2 diabetes.
abstract: To assess the relationship between the length of (GT)n repeats in HO-1 gene promoter and heme oxygenase (HO) enzymatic activity in mononuclear cells with iron (Fe) stores in type 2 diabetic mellitus (DM2) patients and metabolic syndrome (MS) subjects, we studied 163 patients with DM2, 185 with MS, and 120 controls subjects. We evaluated iron status (hemoglobin and serum Fe, ferritin, and transferrin receptor), and we determined the length of (GT)n repeats in HO-1 gene promoter by capillary electrophoresis and HO enzymatic activity in mononuclear cells and assessed the relationship between these results and Fe stores. Only 1/163, 6/185, and 7/120 had iron deficiency anemia in DM2 patients, MS subjects, and controls, respectively. No iron overload (ferritin>200 μg/L) was detected in all the subjects studied. DM2 patients had higher iron deposits, total body iron, and heme oxygenase activity (a suggestion of high oxidative stress condition) than MS subjects and controls. In DM2, we found a positive association between serum iron and HO activity. There were no difference in allelic frequency between the three groups; however, among DM2 and MS patients, the frequency of short/medium (SM) genotype of (GT)n repetition was increased and medium/medium (MM) genotype of (GT)n repetition was lower than controls. These results imply that DM2 patients and individuals with MS carrying SM repeats might have higher susceptibility to develop diabetes consequences. This increased susceptibility could be Fe-mediated oxidative stress.
authors.affiliation: Micronutrient Laboratory, Nutrition Institute and Food Technology (INTA), Department of Medicine, Medicine Faculty, University of Chile, El Líbano 5524, Macul, Santiago, Chile. marredon@inta.cl
authors.forename: Miguel
authors.initials: M
authors.lastname: Arredondo
authors.forename: Marcela
authors.initials: M
authors.lastname: Fuentes
authors.forename: Denisse
authors.initials: D
authors.lastname: Jorquera
authors.forename: Valeria
authors.initials: V
authors.lastname: Candia
authors.forename: Elena
authors.initials: E
authors.lastname: Carrasco
authors.forename: Elba
authors.initials: E
authors.lastname: Leiva
authors.forename: Verónica
authors.initials: V
authors.lastname: Mujica
authors.forename: Eva
authors.initials: E
authors.lastname: Hertrampf
authors.forename: Francisco
authors.initials: F
authors.lastname: Pérez
mesh_terms: D000328:Adult; D000368:Aged; D003924:Diabetes Mellitus, Type 2 / Q000097:blood* / Q000201:enzymology* / Q000378:metabolism; D019075:Electrophoresis, Capillary; D005260:Female; D005293:Ferritins / Q000378:metabolism; D020022:Genetic Predisposition to Disease; D006419:Heme Oxygenase (Decyclizing) / Q000235:genetics / Q000378:metabolism*; D006454:Hemoglobins / Q000378:metabolism; D006801:Humans; D007501:Iron / Q000097:blood* / Q000378:metabolism*; D007963:Leukocytes, Mononuclear / Q000201:enzymology; D008297:Male; D024821:Metabolic Syndrome / Q000097:blood* / Q000201:enzymology* / Q000378:metabolism; D008875:Middle Aged; D011401:Promoter Regions, Genetic; D011990:Receptors, Transferrin / Q000378:metabolism
chemical_list: D006454:Hemoglobins; D011990:Receptors, Transferrin; D005293:Ferritins; D007501:Iron; D006419:Heme Oxygenase (Decyclizing)