title: GG-genotype in the promotor region of uncoupling-protein-1 gene is associated with lower level of dehydroepiandrosterone in type 2 diabetes.
abstract: The A-->G (-3826) point mutation within the distal region of the uncoupling-protein-1 (UCP-1) promoter is possibly involved in the development of obesity, diabetes and related disorders. DHEAS has been found to stimulate expression of UCP-1-mRNA. The aim of our study was to evaluate the prevalence of the three UCP-1 genotypes in type 2 diabetic patients out of a population based sample. Possible associations of A-->G mutation with serum levels of DHEAS and with obesity, diabetes and retinopathy were examined. - In 549 diabetic patients (312 males and 237 females) out of a population-based sample UCP-1 genotype was determined by genomic PCR and Bcl-I-RFLP analysis. Serum levels of DHEAS were measured by ELISA. - Genotype frequencies were: GG genotype, 4.4% (n= 24); AG genotype 37.3% (n=205) and AA genotype 58.3% (n= 320). The genotype groups were comparable with respect to sex, BMI, HbA1c, systolic blood pressure (BP), retinopathy and also to serum levels of C-peptide, leptin and cortisol. Serum levels of DHEAS were lowest in GG-genotype as compared to AG and AA (GG: 1.8+/-1.5 micromol/l, AG: 2.2+/-1.8 micromol/l, AA: 2.6+/-2.1 micromol/l; AA vs AG, AA vs GG: p<0.05). In a multiple linear regression analysis, which controlled for age, C-peptide, cholesterol, systolic BP, BMI, and HbA1c DHEAS was significantly negatively correlated with levels of cholesterol and positively with systolic BP only in females (p<0.05). - Allelic frequency for G in diabetic subjects was 0.23 which was similar as compared to a non-diabetic population examined by us in an earlier study. GG-genotype was associated with low levels of DHEAS in diabetic patients but not with retinopathy. We suggest a role for UCP-1 polymorphism in the pathogenesis of obesity and arteriosclerosis. This hypothesis, however, needs further investigation.
authors.affiliation: Department of Internal Medicine I, University of Regensburg, Germany. Bettina.Zietz@klinik.uni-regensburg.de
authors.forename: B
authors.initials: B
authors.lastname: Zietz
authors.forename: E
authors.initials: E
authors.lastname: Watzlawek
authors.forename: K D
authors.initials: KD
authors.lastname: Palitzsch
authors.forename: J
authors.initials: J
authors.lastname: Schölmerich
authors.forename: A
authors.initials: A
authors.lastname: Schäffler
mesh_terms: D000368:Aged; D000483:Alleles; D001794:Blood Pressure; D002352:Carrier Proteins / Q000235:genetics*; D002784:Cholesterol / Q000097:blood; D003687:Dehydroepiandrosterone / Q000097:blood*; D003924:Diabetes Mellitus, Type 2 / Q000097:blood* / Q000235:genetics*; D005260:Female; D005787:Gene Frequency; D005838:Genotype; D006801:Humans; D007473:Ion Channels; D008297:Male; D008565:Membrane Proteins / Q000235:genetics*; D008875:Middle Aged; D024101:Mitochondrial Proteins; D009154:Mutation; D009765:Obesity / Q000097:blood / Q000235:genetics; D011110:Polymorphism, Genetic; D011401:Promoter Regions, Genetic / Q000235:genetics*; D012727:Sex Characteristics; D013599:Systole; D000071256:Uncoupling Protein 1
chemical_list: D002352:Carrier Proteins; D007473:Ion Channels; D008565:Membrane Proteins; D024101:Mitochondrial Proteins; C000604371:UCP1 protein, human; D000071256:Uncoupling Protein 1; D003687:Dehydroepiandrosterone; D002784:Cholesterol