Imbalance in superoxide dismutase/thioredoxin reductase activities in hypercholesterolemic subjects: relationship with low density lipoprotein oxidation

• Published in: Lipids in health and disease Vol. 11; no. 1; p. 79
• Main Authors: Augusti, Paula Rossini, Ruviaro, Amanda Roggia, Quatrin, Andréia, Somacal, Sabrina, Conterato, Greicy Michelle Marafiga, Vicentini, Juliana Tanara, Duarte, Marta Medeiros Frescura, Emanuelli, Tatiana
• Format: Journal Article
• Language: English
• Published: England BioMed Central Ltd 21.06.2012; BioMed Central; BMC
• Subjects: Adult; Aged; Aryldialkylphosphatase - blood; Atherogenic index; Autoantibodies; Autoantibodies - blood; Autoimmunity; Biomarkers - blood; C-reactive protein; C-Reactive Protein - metabolism; Cardiovascular disease; Cholesterol; Diet; Enzymes; Female; Humans; Hypercholesterolemia; Hypercholesterolemia - blood; Hypercholesterolemia - enzymology; Hypercholesterolemia - immunology; Inflammation; Inflammation Mediators - blood; Lipid Peroxidation; Lipoproteins, LDL - blood; Lipoproteins, LDL - immunology; Low density lipoprotein; Low density lipoproteins; Male; Middle Aged; Oxidation-reduction reaction; Oxidative Stress; Oxidized low density lipoprotein; Physiological aspects; Proteins; Scholarships & fellowships; Superoxide; Superoxide dismutase; Superoxide Dismutase - blood; Thioredoxin reductase; Thioredoxin Reductase 1 - blood; Brazil
• ISSN: 1476-511X; 1476-511X
• DOI: 10.1186/1476-511X-11-79

There is a relationship among hypercholesterolemia, oxidative stress and inflammation in the atherogenesis. Thus, the objective of the present study was to assess paraoxonase (PON1), superoxide dismutase (SOD) and thioredoxin reductase (TrxR-1) activities and their relationship with lipids, oxidative stress and inflammation in subjects with different low density lipoprotein-cholesterol (LDL) levels. Serum lipids, highly sensitive C-reactive protein (hs-CRP), lipid and protein oxidation, oxidized LDL (LDLox) and LDLox autoantibodies (LDLoxAB) levels and enzymes activities were measured in a total of 116 subjects that were divided into the following groups according to their LDL levels: low-LDL group (LDL < 100 mg/dL, n = 23), intermediate-LDL group (LDL 100-160 mg/dL, n = 50) and high-LDL group (LDL > 160 mg/dL, n = 43). The LDLox and hs-CRP levels increased in the high-LDL group (2.7- and 3.7- fold, respectively), whereas the intermediate and high-LDL groups had higher LDLoxAB (2.2- and 3.1-fold) when compared to low-LDL group (p < 0.05). Similarly, SOD activity, the atherogenic index (AI) and protein oxidation were also higher in the intermediate (1.3-, 1.3- and 1.2-fold) and high-LDL (1.6-, 2.3- and 1.6-fold) groups when compared to the low-LDL group (p < 0.05). Lipid oxidation and SOD/TrxR-1 ratio increased only in the high-LDL group (1.3- and 1.6-fold) when compared to the low-LDL group (p < 0.05). The SOD/TrxR-1 ratio was positively correlated to TBARS (r = 0.23, p < 0.05), LDLox (r = 0.18, p < 0.05), LDLoxAB (r = 0.21, p < 0.05), LDL (r = 0.19, p < 0.05) and AI (r = 0.22, p < 0.05). PON1 and TrxR-1 activities were similar among groups. Some oxidative events initiate when LDL levels are clinically acceptable. Moreover, hypercholesterolemic patients have an imbalance in SOD and TrxR-1 activities that is positively associated to LDL oxidation.