title: Peripheral circadian misalignment: contributor to systemic insulin resistance and potential intervention to improve bariatric surgical outcomes.
abstract: Thirteen percent of the world's population suffers from obesity and 39% from being overweight, which correlates with an increase in numerous secondary metabolic complications, such as Type 2 diabetes mellitus. Bariatric surgery is the most effective treatment for severe obesity and results in significant weight loss and the amelioration of obesity-related comorbidities through changes in enteroendocrine activity, caloric intake, and alterations in gut microbiota composition. The circadian system has recently been found to be a critical regulatory component in the control of metabolism and, thus, may potentially play an important role in inappropriate weight gain. Indeed, some behaviors and lifestyle factors associated with an increased risk of obesity are also risk factors for misalignment in the circadian clock system and for the metabolic syndrome. It is thus possible that alterations in peripheral circadian clocks in metabolically relevant tissues are a contributor to the current obesity epidemic. As such, it is plausible that postsurgical alterations in central circadian alignment, as well as peripheral gene expression in metabolic tissues may represent another mechanism for the beneficial effects of bariatric surgery. Bariatric surgery may represent an opportunity to identify changes in the circadian expression of clock genes that have been altered by environmental factors, allowing for a better understanding of the mechanism of action of surgery. These studies could also reveal an overlooked target for behavioral intervention to improve metabolic outcomes following bariatric surgery.
authors.affiliation: Department of Medicine, Section of Endocrinology, Diabetes and Metabolism, University of Chicago, Chicago Illinois;
authors.forename: Kyle N
authors.initials: KN
authors.lastname: Kunze
authors.affiliation: Department of Medicine, Section of Endocrinology, Diabetes and Metabolism, University of Chicago, Chicago Illinois;
authors.forename: Erin C
authors.initials: EC
authors.lastname: Hanlon
authors.affiliation: Department of Surgery, Section of General Surgery, University of Chicago, Chicago Illinois; and Committee on Molecular Metabolism and Nutrition, University of Chicago, Chicago Illinois.
authors.forename: Vivek N
authors.initials: VN
authors.lastname: Prachand
authors.affiliation: Department of Medicine, Section of Endocrinology, Diabetes and Metabolism, University of Chicago, Chicago Illinois; Committee on Molecular Metabolism and Nutrition, University of Chicago, Chicago Illinois mbrady1@uchicago.edu.
authors.forename: Matthew J
authors.initials: MJ
authors.lastname: Brady
mesh_terms: D050110:Bariatric Surgery; D056926:CLOCK Proteins / Q000378:metabolism; D002940:Circadian Rhythm; D006801:Humans; D007333:Insulin Resistance; D008954:Models, Biological; D009765:Obesity / Q000503:physiopathology* / Q000601:surgery*; D011379:Prognosis; D016896:Treatment Outcome
chemical_list: D056926:CLOCK Proteins