ORIGINAL ARTICLE Glutathione Peroxidase 3 Serum Levels and GPX3 Gene Polymorphisms in Subjects with Metabolic Syndrome Q3 Blanca G. Baez-Duarte, a Francisco Mendoza-Carrera, b Alejandra Garc  ıa-Zapien, b Silvia E. Flores-Mart  ınez, b Jos eS anchez-Corona, b Irma Zamora-Ginez, a Enrique Torres-Rasgado, a Bertha A. Le on-Ch avez, c Ricardo P erez-Fuentes, a,d and for the Multidisciplinary Research Group on Diabetes of the Instituto Mexicano del Seguro Social a Facultad de Medicina, Benem erita Universidad Aut onoma de Puebla (BUAP), M exico b Centro de Investigaci on Biom edica de Occidente (CIBO), Instituto Mexicano del Seguro Social (IMSS), Guadalajara, Jalisco, M exico c Facultad de Ciencias Qu ımicas, BUAP, M exico Q1 d Centro de Investigaci on Biom edica de Oriente (CIBIOR), IMSS, Atlixco, Puebla, M exico Received for publication November 22, 2013; accepted April 28, 2014 (ARCMED-D-13-00660). Background and Aims. Glutathione peroxidase 3 (GPx3) plays a main role in re- moving hydro- and lipoperoxides from the body. Changes in concentration and several single-nucleotide polymorphisms (SNP) at the GPX3 gene have been associ- ated with vascular diseases, but the relationship of GPx3 with metabolic syndrome (MetS) remains unexplored. We undertook this study to determine the association of GPx3 serum levels and several GPX3 SNPs with the presence of MetS in Mexican subjects. Methods. Clinical, biochemical, and anthropometric evaluation were conducted in 426 subjects assigned to three groups: control (n 5 42); risk group (RG, n 5 200), and MetS group (n 5 184). Insulin sensitivity (IS) and cardiovascular risk were determined by the QUICKI and TG/HDL-C index, respectively. Serum GPx3 was determined by enzyme immunoassay and polymorphisms within GPX3 gene were identified by nucleotide sequencing. Results. MetS group showed low IS and increased cardiovascular risk with respect to controls as well as higher GPx3 serum levels (172.9  32.2 vs. 145.6  24.8 ng/dL; p !0.05). Only three of the ten GPX3 SNPs screened were polymorphic with two haplotypes observed (CCT and TTAers8177404, rs8177406, and rs8177409), indicating tight linkage disequilibrium in this genetic region. No differ- ences for either genotype or allele frequencies among groups were observed, but rs8177409 (allele T) was associated with cardiovascular risk (odds ratio [OR], 4.5; p 5 0.0125). Conclusion. This study shows that serum levels of GPx3 are increased in subjects with MetS and that rs8177409 SNP was associated with cardiovascular risk in a Mexican pop- ulation. Ó 2014 IMSS. Published by Elsevier Inc. Key Words: Metabolic syndrome, Glutathione peroxidase 3, Cardiovascular risk, GPX3$gene polymorphisms. Introduction Metabolic syndrome (MetS) is considered a public health problem worldwide, especially in ‘‘westernized’’ countries (1). The parallel increase in the prevalence of overweight/ obesity and MetS is a global phenomenon and Mexico is ARCMED1917_proof ■ 9-5-2014 16-42-7 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 Address reprint requests to: Ricardo P erez-Fuentes, Ph.D., Instituto Mexicano del Seguro Social, Km 4.5 Carretera Federal Atlixco-Metepec, 62340 Atlixco, Puebla, M exico. Phone numbers: (þ52) (222) 246 3704 and (þ52) (222) 194 5758; FAX: NEEDED Q2 ; E-mail: rycardoperez@ hotmail.com 0188-4409/$ - see front matter. Copyright Ó 2014 IMSS. Published by Elsevier Inc. http://dx.doi.org/10.1016/j.arcmed.2014.05.001 Archives of Medical Research - (2014) -