Impairment of serum albumin antioxidant properties in obstructive sleep apnoea syndrome

Abstract

Antioxidant counteraction of oxidative stress has been poorly explored in obstructive sleep apnoea (OSA). Serum albumin is a major antioxidant agent and structural modifications induced by glucose or free radicals impair its antioxidant properties.The aim of the present study was to compare antioxidant capacities and structural changes of albumin in nonobese OSA patients and healthy volunteers.Albumin structural changes were studied by quenching of fluorescence in the presence of acrylamide. Albumin thiols and fructosamines, reflecting oxidation-and glycation-induced changes in serum albumin, respectively, were assessed. Albumin structural changes were demonstrated by a significant decrease in quenching of fluorescence in OSA patients. Oxidation, resulting in a significant decrease in thiol groups (3.7¡0.7 versus 2.3¡0.4 mmol?g -1 protein), and glycation, associated with a significant increase in fructosamines (226.6¡27 versus 286¡44.4 mmol?L -1 ), were found when comparing healthy volunteers with OSA patients. There was a significant relationship between both parameters and sleep apnoea severity. After continuous positive airway pressure intervention, albumin thiol groups were reassessed in seven of the 16 OSA patients and increased significantly from 2.25¡0.39 to 2.79¡0.31 mmol?g -1 protein.Obstructive sleep apnoea patients demonstrated a reduction in serum albumin antioxidant properties that may aggravate oxidative stress and, thus, contribute to cardiovascular and metabolic morbidities.

Intermittent hypoxia and sleep-disordered breathing: current concepts and perspectives

“…In the same study, continuous positive airway pressure (CPAP) treatment normalised total antioxidant status [23]. In 2008, impairment of albumin antioxidant properties independent of body mass index (BMI) and related only to OSA severity has been demonstrated [24].…”

Human serum albumin: From bench to bedside

“…This reflects the impaired anti-oxidant HSA activity, which is associated with the enhanced glycation level of HSA in patients affected by this sleep disorder (Faure et al, 2008b). 7.…”

Impact of Obstructive Sleep Apnea on Myocardial Tissue Perfusion in Patients With ST-Segment Elevation Myocardial Infarction

“…37 Faure et al demonstrated a decrease in albumin antioxidant properties in non-obese OSA patients when compared with control subjects. 38 Thus, it is highly probable that the increased oxidative stress under reduced antioxidant capacity may have resulted in more severe coronary microvascular injury in the present OSA patients.…”