Heat‐shock protein 70: expression in monocytes of patients with sleep apnoea and association with oxidative stress and tumour necrosis factor‐α

Summary Obstructive sleep apnoea (OSA) is associated with a variety of nightly stresses, including intermittent hypoxaemia, oxidative stress and sleep fragmentation. Heat‐shock proteins (HSPs) are upregulated in response to an array of environmental and metabolic stresses. We hypothesized that the OSA‐related stresses would affect the expression of HSP70 in monocytes. Basal (30 min, at 37 °C), heat stress‐induced HSP70 (30 min, at 43 °C) and basal tumour necrosis factor‐α (TNF‐α) were determined by flow cytometry in monocytes of 10 patients with OSA and 10 controls matched by age, gender and body mass index. Oxidative stress was determined by thiobarbituric acid‐reactive substances (TBARS) and antioxidant paraoxonase‐1 activity. Basal HSP70 expression was 1.8‐fold higher in patients with OSA as compared with controls (P