Combined Effects of Acute Restraint Stress and Rapid Eye Movement (REM) Sleep Deprivation on Renal Inflammation in Female Wistar Rats

Abstract

Psychological stress which is on the increase daily has emerged as a major contributor to the onset and progression of kidney disorders by promoting established risk factors such as hypertension and diabetes. Furthermore, stress is often associated with sleep loss and both factors are known to disrupt oxidative balance and pro and anti-inflammatory balance contributing to organ dysfunction. Despite extensive studies on their individual effects on the kidney, there are limited studies regarding the combined impact of acute stress and REM sleep deprivation in regards to renal inflammation.  A total number of 24 female Wistar rats weighing 180-220 g were randomly categorized into 4 groups with 6 rats in each group: Control (CTL ) were given feed and water ad libitum, Restraint stress (RSS) animals were restrained with wire mesh for 30 minutes each day for 28 days, Sleep deprivation (SSD) animals were subjected  to 6 hours sleep deprivation every two days for 28 days using inverted flower pot, Restraint stress + Sleep deprivation (RSD) were exposure to both restraint stress and sleep deprivation. Twenty four hours after the last procedures, all rats were anesthetized and their kidneys were excised, weighed and homogenized for biochemical assays (Nitric oxide (NO), Myeloperoxidase (MPO) and Tumor necrosis factor-α (TNF-α). The results showed that body weight changes was significantly reduced (p<0.05) while NO, MPO and TNF-α levels were significantly higher (p<0.05) in the RSD group when compared with other groups. In conclusion, concomitant exposures to restraint stress and sleep deprivation triggered renal inflammation, indicating that interaction between psychological stress and sleep loss may accelerate kidney dysfunction.