THE COMBINED EFFECTS OF A TYPICAL AMERICAN-STYLE DIET AND CHRONIC SLEEP RESTRICTION ON ANXIETY-LIKE BEHAVIOR IN MICE

Abstract

Alzheimer's disease (AD) currently afflicts well over six million people in the United States, and this number is projected to increase exponentially in the coming years. While much remains to be understood about the causes and pathogenesis of AD, two potential risk factors are chronic insufficient sleep and long-term consumption of an unhealthy diet. Both of these lifestyle factors are often studied separately, and evidence suggests that each has negative impacts on brain health and cognitive function, perhaps due to increases in inflammation, which itself is associated with increased anxiety and cognitive dysfunction. The current study investigated the combined effects of long-term consumption of a typical American-style diet (TAD) and six weeks of chronic sleep restriction on locomotor activity and anxiety-like behavior in male and female wild-type mice not otherwise predisposed to disease pathology. Female mice that underwent sleep restriction and consumed the TAD displayed greater anxiety-like behavior compared to mice that the TAD and did not undergo sleep restriction. This difference was not observed in male mice. Furthermore, male mice that underwent chronic sleep restriction displayed greater locomotor activity compared to controls. These differences were not observed in females. Given the prevalence of AD and the projected rise in AD cases, understanding how controllable lifestyle or environmental factors can increase AD risk is essential. Importantly, as AD is more prevalent in women compared to men, it is imperative that research efforts utilize male and female animals seek to understand the mechanisms driving this phenomenon.