Serum levels of retinol binding protein 4 in women with different levels of adiposity and glucose tolerance

Abstract

Objective: Retinol-binding protein 4 (RBP4) is an adipokine responsible for vitamin A (retinol) transportation. Studies associated RBP4 increased levels with severity of type 2 diabetes mellitus (T2DM) and insulin resistance (IR). The study aimed to quantify RBP4 serum standards in women with a wide range of body mass index (BMI) and glucose tolerance level. Subjects and methods: Cross-sectional study was performed with 139 women divided into three groups: Group 1 (lean-control, n = 45) and Group 2 (obese, n = 53) with normal glucose tolerance and group 3 (obese with T2DM, n = 41), called G1, G2 and G3. Were assessed clinical, biochemical, anthropometric and body composition parameters. Results: According to data analysis, we obtained in G1 higher RBP4 levels (104.8 ± 76.8 ng/mL) when compared to G2 (87.9 ± 38 ng/mL) and G3 (72.2 ± 15.6 ng/mL) levels. Also, were found: in G1 positive correlations of RBP4 with BMI (r = 0.253), glycated hemoglobin (r = 0.378) and fasting insulin (r = 0.336); in G2 with glycated hemoglobin (r = 0.489); in G3 with glycated hemoglobin (r = 0.330), fasting glucose (r = 0.463), HOMA-IR (r = 0.481). Conclusions: Although RBP4 have shown lower levels in diabetic and obese, a strong correlation with HOMA-IR index highlights that, in our study, there is growing IR when there is an increasing in RBP4 levels. Arq Bras Endocrinol Metab. 2014;58(7):709-14 Keywords Obesity; metabolic syndrome; insulin resistance; women; premenopause RESUMO Objetivo: A proteína carreadora do retinol 4 (RBP4) é uma adipocina responsável pelo transporte de vitamina A (retinol). Estudos associam os níveis aumentados de RBP4 com a gravidade do diabetes melito tipo 2 (DM2) e resistência à insulina (RI). O objetivo deste estudo foi investigar como esses níveis se comportam em mulheres com ampla variação do índice de massa corporal (IMC) e tolerância à glicose. Sujeitos e métodos: Estudo transversal realizado com 139 mulheres, divididas em três grupos: Grupo 1 (controles-magras; n = 45) e Grupo 2 (obesas; n = 53), com tolerância normal à glicose; Grupo 3 (obesas DM2; n = 41), denominados G1, G2 e G3. Foram avaliados parâmetros clínicos, bioquímicos, antropométricos e composição corporal. Resultados: De acordo com a análise dos dados, obtivemos em G1 maiores níveis de RBP4 (104,8 ± 76,8 ng/mL) em comparação ao G2 (87,9 ± 38 ng/mL) e G3 (72,2 ± 15,6 ng/mL). Também foram encontradas correlações positivas entre RBP4 e IMC (r = 0,253), hemoglobina glicada (r = 0,378) e insulinemia de jejum (r = 0,336); em G2 com hemoglobina glicada (r = 0,489); G3 com hemoglobina glicada (r = 0,330), insulinemia de jejum (r = 0,463) e HOMA-IR (r = 0,481). Conclusões: Embora a RBP4 tenha apresentado níveis menores em pacientes diabéticas e obesas, a forte correlação com o índice HOMA-IR deixa claro que, em nosso estudo, há crescente RI quando os níveis dessa proteína também são crescentes. Arq Bras Endocrinol Metab. 2014;58(7):709-14 Descritores Obesidade; síndrome metabólica; resistência à insulina; mulheres; pré-menopausa

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Association of retinol binding protein 4 and transthyretin with triglyceride levels and insulin resistance in rural thais with high type 2 diabetes risk

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Assessment of Neutrophil Gelatinase-Associated Lipocalin (NGAL) and Retinol-Binding Protein 4 (RBP4) in Type 2 Diabetic Patients with Nephropathy

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