Increase in serum haptoglobin and apolipoprotein M in patients with obstructive sleep apnoea

Abstract

Summary Obstructive sleep apnoea (OSA) is a common syndrome, which is associated with a number of medical problems that impact morbidity and mortality. Although the precise mechanisms that underlie these associations are not fully understood, previous studies have suggested that patients with OSA show elevations of several biomarkers that are associated with cardiovascular risk. This study was undertaken to identify serum proteins associated with OSA by using a proteomics technique and to examine changes in identified protein levels after continuous positive airway pressure treatment. The study participants consisted of 40 male patients (aged 40–49 years) with severe OSA and 34 male control subjects matched for age and body mass index. All subjects underwent polysomnography. Using a proteomics approach, we identified nine proteins that were differentially expressed in patients with severe OSA and controls. Three of these nine proteins, haptoglobin, paraoxonase‐1 and apolipoprotein M, were quantified by using enzyme‐linked immunosorbent assays, kinetic assays and by using Western blotting. Multiple regression analysis showed that haptoglobin and apolipoprotein M levels are independently related to apnoea–hypopnoea index (P < 0.01). A further study is required to determine the nature of associations between these identified proteins and OSA in a large population.

Overview of proteomics studies in obstructive sleep apnea

“…Except serum paraoxonase (PON1) and alpha-ferrous-carbonmonoxy, all identified proteins were highly abundant. These findings were validated by western blotting and ELISA techniques for the haptogolobin, PON1, and apo M [56]. It is important to note that levels of haptoglobin were significantly higher in all patients with OSA.…”

“…According to our knowledge, Kim and co-workers have been the first to analyze serum proteome of OSA adult subjects [56]. Criteria of OSA severity were based on AHI and co-related clinical symptoms.…”

“…This behavior was not followed by the other two validated proteins. Haptoglobin and apo M were found to be independently associated with AHI [56]. …”

Evaluation of C-reactive protein, Haptoglobin and cardiac troponin 1 levels in brachycephalic dogs with upper airway obstructive syndrome

“…Some epidemiological studies have linked high haptoglobin (Hp) levels with a greater incidence of myocardial infarct [16]. Kim and others [16] have reported that human patients with OSAS have higher levels of Hp, which fell after medical treatment with a continuous positive airway pressure device.…”

Serum from obstructive sleep apnea patients induces inflammatory responses in coronary artery endothelial cells

“…Serum proteomics has been conducted on only a limited basis, revealing potential increases in a number of known proteins, such as fibronectin and ApoB100 in OSA patients [45]. Another study utilizing 2D electrophoresis noted increased serum levels of haptoglobins and reduced levels of paraoxonase-1 in OSA patients [46]. However, both proteomics studies were unable to examine modified (fragmented or adducted) proteins, and were they unable to link findings to specific functional outcomes.…”