AUTHOR=Atkin Stephen L. , Ramachandran Vimal , Yousri Noha A. , Benurwar Manasi , Simper Steven C. , McKinlay Rodrick , Adams Ted D. , Najafi-Shoushtari S. Hani , Hunt Steven C. TITLE=Changes in Blood microRNA Expression and Early Metabolic Responsiveness 21 Days Following Bariatric Surgery JOURNAL=Frontiers in Endocrinology VOLUME=9 YEAR=2019 URL=https://www.frontiersin.org/journals/endocrinology/articles/10.3389/fendo.2018.00773 DOI=10.3389/fendo.2018.00773 ISSN=1664-2392 ABSTRACT=

Background: Early metabolic responses following bariatric surgery appear greater than expected given the initial weight loss and coincide with improvement in diabetes. We hypothesized that small non-coding microRNA changes might contribute to regulating mechanisms for metabolic changes and weight loss in patients with severe obesity and diabetes.

Methods: Twenty-nine type 2 patients with severe obesity (mean BMI 46.2 kg/m2) and diabetes underwent Roux-en-Y gastric bypass (RYGB) surgery. Clinical measurements and fasting blood samples were taken preoperatively and at day 21 postoperatively. Normalization of fasting glucose and HbA1c following bariatric surgery (short-term diabetes remission) was defined as withdrawal of anti-diabetic medication and fasting glucose < 100 mg/dL (5.6 mmol/L) or HbA1c < 6.0%. MicroRNA expression was determined by quantitative polymerase chain reaction and tested for significant changes after surgery.

Results: BMI decreased by 3.8 kg/m2 21 days postoperatively. Eighteen of 29 RYGB (62%) had short-term diabetes remission. Changes from pre- to post-surgery in 32 of 175 microRNAs were nominally significant (p < 0.05). Following multiple comparison adjustment, changes in seven microRNAs remained significant: miR-7-5p, let-7f-5p, miR-15b-5p, let-7i-5p, miR-320c, miR-205-5p, and miR-335-5p. Four pathways were over-represented by these seven microRNAs, including diabetes and insulin resistance pathways.

Conclusion: Seven microRNAs showed significant changes 21 days after bariatric surgery. Functional pathways of the altered microRNAs were associated with diabetes-, pituitary-, and liver-related disease, with expression in natural killer cells, and pivotal intestinal pathology suggesting possible mechanistic roles in early diabetes responses following bariatric surgery.