Liver blood dynamics after bariatric surgery: the effects of mixed-meal test and incretin infusions. Issue 7 (July 2018)

• Record Type: Journal Article
• Authors: Honka, Henri; Koffert, Jukka; Kauhanen, Saila; Kudomi, Nobuyuki; Hurme, Saija; Mari, Andrea; Lindqvist, Andreas; Wierup, Nils; Parkkola, Riitta; Groop, Leif; Nuutila, Pirjo
• Is Part Of: Endocrine connections. Volume 7:Issue 7(2018)
• Page Start: 888
• Page End: 896
• Publication Date: 2018-07
• Subjects: portal vein blood flow -- hepatic blood volume -- glucose-dependent insulinotropic polypeptide -- bariatric surgery -- positron emission tomography; Endocrinology -- Periodicals; 616.4005
• DOI: 10.1530/EC-18-0234
• Languages: English
• ISSNs: 2049-3614

Abstract

Abstract : Aims/hypothesis: The mechanisms for improved glycemic control after bariatric surgery in subjects with type 2 diabetes (T2D) are not fully known. We hypothesized that dynamic hepatic blood responses to a mixed-meal are changed after bariatric surgery in parallel with an improvement in glucose tolerance. Methods: A total of ten morbidly obese subjects with T2D were recruited to receive a mixed-meal and a glucose-dependent insulinotropic polypeptide (GIP) infusion before and early after (within a median of less than three months) bariatric surgery, and hepatic blood flow and volume (HBV) were measured repeatedly with combined positron emission tomography/MRI. Ten lean non-diabetic individuals served as controls. Results: Bariatric surgery leads to a significant decrease in weight, accompanied with an improved β-cell function and glucagon-like peptide 1 (GLP-1) secretion, and a reduction in liver volume. Blood flow in portal vein (PV) was increased by 1.65-fold ( P = 0.026) in response to a mixed-meal in subjects after surgery, while HBV decreased in all groups ( P < 0.001). When the effect of GIP infusion was tested separately, no change in hepatic arterial and PV flow was observed, but HBV decreased as seen during the mixed-meal test. Conclusions/interpretation: Early after bariatric surgery, PV flow response to a mixed-meal is augmented, improving digestion and nutrient absorption. GIP influences the post-prandial reduction in HBV thereby diverting blood to the extrahepatic sites.