Erectile dysfunction and diabetes: Association with the impairment of lipid metabolism and oxidative stress

Objectives: To test the hypothesis that exists an association of non-diabetic and diabetic patients suffering from erectile dysfunction (ED) with lipid metabolism and oxidative stress. Design and methods: Clinical and laboratory characteristics in non-diabetic (n = 30, middle age range: 41-55.5 years; n = 25, old age range: 55.5-73), diabetic ED patients (n = 30, age range: 55.5-75 years) and diabetic patients (n = 25, age range: 56-73.25), were investigated. Proteomic analysis was performed to identify differentially expressed plasma proteins and to evaluate their oxidative post translational modifications. Results: A decreased level of high-density lipoproteins in all ED patients (P<0.001, C.I. 0.046-0.10), was detected by routine laboratory tests. Proteomic analysis showed a significant decreased expression (P < 0.05) of 5 apolipoproteins (i.e. apolipoprotein H, apolipoprotein A4, apolipoprotein J, apolipoprotein E and apolipoprotein Al) and zinc-alpha-2-glycoprotein, 50% of which are more oxidized proteins. Exclusively for diabetic ED patients, oxidative posttranslational modifications for prealbumin, serum albumin, serum transferrin and haptoglobin markedly increased. Conclusions: Showing evidence for decreased expression of apolipoproteins in ED and the remarkable enhancement of oxidative posttranslational modifications in diabetes-associated ED, considering type 2 diabetes mellitus and age as independent risk factors involved in the ED pathogenesis, lipid metabolism and oxidative stress appear to exert a complex interplay in the disease. (C) 2015 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.