Authors: Hina Y Bhutta Tara E Deelman Stanley W Ashley David B Rhoads Ali Tavakkoli
Publish Date: 2013/04/30
Volume: 58, Issue: 6, Pages: 1537-1545
Abstract
Intestinal absorptive capacity shows a circadian rhythm synchronized with eating patterns Disrupting these coordinated rhythms eg with shift work may contribute to metabolic disease Circadian expression of nutrient transporters has not been studied in metabolic disease We studied the circadian rhythm of intestinal transporter sodium glucose cotransporter type 1 SGLT1 in an obese diabetic ratWe compared obese Zucker diabetic fatty ZDF rats to lean ZDF littermates Temporal feeding patterns were assessed then rats were harvested at Zeitgeber ZT ZT0 = 700 am 3 9 or 15 to measure insulin resistance SGLT1 expression and intestinal glucose absorption capacity Regulators of SGLT1 sweet taste receptor T1R2/3 clock genes were measured to elucidate underlying mechanismsBoth groups exhibited altered circadian food intake Obese ZDF rats lost circadian rhythmicity of SGLT1 mRNA expression and functional activity Lean ZDF rats maintained rhythmicity of SGLT1 mRNA expression but that of functional glucose absorption was blunted Circadian rhythms of intestinal clock genes were maintained in both groups Neither group had discernible rhythms of intestinal GLUT2 glucose transporter or T1R2 sweet taste receptor component mRNA expression In summary lean and obese ZDF rats exhibited similar disruptions in circadian feeding Glucose intolerance was evident in lean rats but only obese rats further developed diabetes and exhibited disrupted circadian rhythmicity of both SGLT1 mRNA expression and functionWe thank Jan Rounds for invaluable managerial support and Dr Carel Le Roux at Imperial College London UK for his role as coeducational supervisor to HB The manuscript has been presented as an oral presentation at the Society of Academic and Research Surgery Nottingham UK Jan 2012 and the Academic Surgical Congress Las Vegas Feb 2012 It was published in abstract form only in a supplementary issue of Journal of Surgical Research as related to this meeting This study was funded by National Institute of Health Grant 1 R01 DK084064 AT and Harvard Clinical and Translational Science Center 5 KL2 RR025757 ATHY Bhutta TE Deelman SW Ashley and DB Rhoads have no conflicts of interest A Tavakkoli has an equity interest in Avaxia Biologics a company that is developing oral antibodies for treatment of intestinal disorders with potential applications for treatment of diabetes and obesity AT’s interests were reviewed and are managed by the Brigham and Women’s Hospital and Partners HealthCare in accordance with their conflictofinterest policies
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