| 1. |
- Honka, Henri, et al.
(författare)
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Bariatric surgery enhances splanchnic vascular responses in patients with type 2 diabetes
- 2017
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Ingår i: Diabetes. - : American Diabetes Association. - 0012-1797 .- 1939-327X. ; 66:4, s. 880-885
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Tidskriftsartikel (refereegranskat)abstract
- Bariatric surgery results in notable weight loss and alleviates hyperglycemia in patients with type 2 diabetes (T2D). We aimed to characterize the vascular effects of a mixedmeal and infusion of exogenous glucose-dependent insulinotropic polypeptide (GIP) in the splanchnic region in 10 obese patients with T2D before and after bariatric surgery and in 10 lean control subjects. The experiments were carried out on two separate days. Pancreatic and intestinal blood flow (BF) were measured at baseline, 20 min, and 50 min with 15O-water by using positron emission tomography and MRI. Before surgery, pancreatic and intestinal BF responses to a mixed meal did not differ between obese and lean control subjects. Compared with presurgery, the mixed meal induced a greater increase in plasma glucose, insulin, and GIP concentrations after surgery, which was accompanied by a marked augmentation of pancreatic and intestinal BF responses. GIP infusion decreased pancreatic but increased small intestinal BF similarly in all groups both before and after surgery. Taken together, these results demonstrate that bariatric surgery leads to enhanced splanchnic vascular responses as a likely consequence of rapid glucose appearance and GIP hypersecretion.
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| 2. |
- Honka, Henri, et al.
(författare)
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Liver blood dynamics after bariatric surgery : The effects of mixed-meal test and incretin infusions
- 2018
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Ingår i: Endocrine Connections. - 2049-3614. ; 7:7, s. 888-896
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Tidskriftsartikel (refereegranskat)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.
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| 3. |
- Koffert, Jukka, et al.
(författare)
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Effects of meal and incretins in the regulation of splanchnic blood flow
- 2017
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Ingår i: Endocrine Connections. - 2049-3614. ; 6:3, s. 179-187
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Tidskriftsartikel (refereegranskat)abstract
- Objective: Meal ingestion is followed by a redistribution of blood flow (BF) within the splanchnic region contributing to nutrient absorption, insulin secretion and glucose disposal, but factors regulating this phenomenon in humans are poorly known. The aim of the present study was to evaluate the organ-specific changes in BF during a mixed-meal and incretin infusions. Design: A non-randomized intervention study of 10 healthy adults to study splanchnic BF regulation was performed. Methods: Effects of glucose-dependent insulinotrophic polypeptide (GIP) and glucagon-like peptide 1 (GLP-1) infusions and mixed-meal were tested in 10 healthy, glucose tolerant subjects using PET-MRI multimodal imaging technology. Intestinal and pancreatic BF and blood volume (BV) were measured with 15O-water and 15O-carbon monoxide, respectively. Results: Ingestion of a mixed-meal led to an increase in pancreatic and jejunal BF, whereas duodenal BF was unchanged. Infusion of GIP and GLP-1 reduced BF in the pancreas. However, GIP infusion doubled blood flow in the jejunum with no effect of GLP-1. Conclusion: Together, our data suggest that meal ingestion leads to increases in pancreatic BF accompanied by a GIP-mediated increase in jejunal but not duodenal blood flow.
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| 4. |
- Saari, Teemu, et al.
(författare)
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Obesity-associated Blunted Subcutaneous Adipose Tissue Blood Flow After Meal Improves After Bariatric Surgery
- 2022
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Ingår i: Journal of Clinical Endocrinology and Metabolism. - : The Endocrine Society. - 0021-972X .- 1945-7197. ; 107:7, s. 1930-1938
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Tidskriftsartikel (refereegranskat)abstract
- Context: Glucose-dependent insulinotropic peptide (GIP) and meal ingestion increase subcutaneous adipose tissue (SAT) perfusion in healthy individuals. The effects of GIP and a meal on visceral adipose tissue (VAT) perfusion are unclear. Objective: Our aim was to investigate the effects of meal and GIP on VAT and SAT perfusion in obese individuals with type 2 diabetes mellitus (T2DM) before and after bariatric surgery. Methods: We recruited 10 obese individuals with T2DM scheduled for bariatric surgery and 10 control individuals. Participants were studied under 2 stimulations: meal ingestion and GIP infusion. SAT and VAT perfusion was measured using 15O-H2O positron emission tomography-magnetic resonance imaging at 3 time points: baseline, 20 minutes, and 50 minutes after the start of stimulation. Obese individuals were studied before and after bariatric surgery. Results: Before bariatric surgery the responses of SAT perfusion to meal (P = .04) and GIP-infusion (P = .002) were blunted in the obese participants compared to controls. VAT perfusion response did not differ between obese and control individuals after a meal or GIP infusion. After bariatric surgery SAT perfusion response to a meal was similar to that of controls. SAT perfusion response to GIP administration remained lower in the operated-on than control participants. There was no change in VAT perfusion response after bariatric surgery. Conclusion: The vasodilating effects of GIP and meal are blunted in SAT but not in VAT in obese individuals with T2DM. Bariatric surgery improves the effects of a meal on SAT perfusion, but not the effects of GIP. Postprandial increase in SAT perfusion after bariatric surgery seems to be regulated in a GIP-independent manner.
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