Night shifts may contribute to weight gain Researchers studied the natural sleep cycle. They are discovering more about how changes to a person's night rest upset other systems in the body, resulting in weight gain. Health © Thinkstock Cases of obesity and type 2 diabetes are continually increasing in Europe at great social and economic cost. Research is being conducted to more thoroughly understand their causes and find pharmacological solutions. One possible solution that was explored involved the relationship between the nuclear receptor Rev-erba and metabolic processes. Rev-erba is a circadian clock component that is said to form a feedback loop that aids and regulates clock function. Higher rates of obesity and diabetes are associated with shift work or irregular sleeping patterns, suggesting a relationship between circadian clockwork disruption and disrupted metabolic processes. It is important to understand the key components, such as Rev-erba, in the coordination of circadian and metabolic cycles as it can offer new solutions. The GLUCOLOCK project researched this, confirming the relationship between the clock component Rev-erba and metabolic processes. First, the project's research, as others before, showed that Rev-erba is involved in lipid metabolism, bile acid synthesis and adipogenesis. Rev-erba was also shown to regulate the glucogenesis pathway, suggesting it is involved in glucose metabolism. Research also showed that Rev-erba deficiency in skeletal muscle leads to reduced mitochondrial content and oxidative function, causing decreased exercise capacity. Conversely, Rev-erba overexpressions increased mitochondrial content and improved respiratory capacity. The pharmacological activation of Rev-erba increased respiration and exercise capacity. The whole of the project's findings led to the conclusion that Rev-erba, as a clock component, adapts mitochondrial activity to the circadian time. Rev-erba was also found to improve muscle oxidative function by modulating gene networks controlling mitochondrial number and function. It is established that Rev-erba, as a crucial clock component and clock-regulated gene, is important to metabolic processes and potentially useful as a pharmacological target. These findings provide a basis of molecular evidence that can be used to discover new treatments that consider circadian rhythms, for mitochondrial-related metabolic disorders. Keywords Night shift, weight gain, sleep cycle, type-2 diabetes, Rev-erba, metabolic processes, circadian clock, sleeping patterns, lipid metabolism, bile acid synthesis, adipogenesis, glucogenesis, exercise capacity, respiratory capacity, metabolic disorder
