Effects of hyperbaric oxygen on inflammation and oxidative stress in PCPA-induced insomnia rat models

Abstract To clarify the effect and mechanism of hyperbaric oxygen (HBO) on insomnia, SD rats were divided randomly into PCPA, HBO+PCPA and Control group (n=8). Rat insomnia model was established by intraperitoneal injection of para-chlorophenylalanine (PCPA), then 2.0ATA-60min HBO was given. After the intervention, general behavior, sleep status, brain tissue pathology, serum inflammatory and oxidative stress molecules were measured. Compared with the Control group, the rats in the PCPA group showed circadian rhythm reversal, daytime sleep time reduction, weight loss and temper irritability. Sleep latency was significantly prolonged and the sleep duration was significantly shortened in PCPA group. All above changes were significantly improved by HBO intervention. Positive Nissl staining in hippocampus, prefrontal cortex and hypothalamus of PCPA group was largely decreased compared with the controls, which was obviously reversed in HBO+PCPA group. Moreover, serum IL-1β, IL-6, IL-17A, TNF-Α and MDA were markedly increased, while IL-10, IL-12p70 and SOD were significantly decreased in PCPA group, compared to the Controls. When compared with PCPA group, HBO intervention can significantly decrease the levels of IL-1β, IL-6, IL-17A, TNF-Α and MDA, while significantly increased the levels of IL-10, IL-12p70 and SOD in serum. HBO can relieve PCPA-induced rat insomnia symptoms, reduce inflammation and oxidative stress injury in vivo, which is one of mechanisms of HBO treatment for insomnia.