Effect of bariatric surgery on liver glucose metabolism in morbidly obese diabetic and non-diabetic patients.
OBJECTIVE
Bariatric surgery reduces weight and improves glucose metabolism in obese patients. We investigated the effects of bariatric surgery on hepatic insulin sensitivity.


METHODS
Twenty-three morbidly obese (nine diabetic and fourteen non-diabetic) patients and ten healthy, lean control subjects were studied using positron emission tomography to assess hepatic glucose uptake in the fasting state and during euglycemic hyperinsulinemia. Magnetic resonance spectroscopy was performed to measure liver fat content and magnetic resonance imaging to obtain liver volume. Obese patients were studied before bariatric surgery (either sleeve gastrectomy or Roux-en-Y gastric bypass) and six months after surgery.


RESULTS
Insulin-induced hepatic glucose uptake was increased by 33% in non-diabetic and by 36% in diabetic patients at follow-up compared with baseline, but not totally normalized. The liver fat content was reduced by 76%, liver volume by 26% and endogenous glucose production by 19% in non-diabetic patients. The respective changes in diabetic patients were 73%, 24%, and 25%. Postoperatively, liver fat content and endogenous glucose production were almost normalized to lean controls, but liver volume remained greater than in control subjects.


CONCLUSIONS
This study shows that bariatric surgery leads to a significant improvement in hepatic insulin sensitivity: insulin-stimulated hepatic glucose uptake was improved and endogenous glucose production reduced when measured, six-months, after surgery. These metabolic effects were accompanied by a marked reduction in hepatic volume and fat content. Overall, the gain in hepatic insulin sensitivity in diabetic patients was quite similar to non-diabetic patients for the same weight reduction.
Turku PET Centre, Turku, Finland; Department of Medicine, Turku University Hospital, Turku, Finland.
Heidi
H
Immonen
Turku PET Centre, Turku, Finland.
Jarna C
JC
Hannukainen
Institute of Clinical Physiology, National Research Council, Pisa, Italy.
Patricia
P
Iozzo
Turku PET Centre, Turku, Finland; Department of Medicine, Turku University Hospital, Turku, Finland.
Minna
M
Soinio
Department of Surgery, Turku University Hospital, Turku, Finland.
Paulina
P
Salminen
Turku PET Centre, Turku, Finland.
Virva
V
Saunavaara
Turku PET Centre, Turku, Finland; Department of Radiology, Turku University Hospital, Turku, Finland.
Ronald
R
Borra
Department of Radiology, Turku University Hospital, Turku, Finland.
Riitta
R
Parkkola
Institute of Biomedical Engineering, Padua, Italy.
Andrea
A
Mari
Department of Clinical Chemistry, Finlab Laboratories, Tampere University Hospital and University of Tampere School of Medicine, Finland.
Terho
T
Lehtimäki
Turku PET Centre, Turku, Finland.
Tam
T
Pham
Department of Pathology, Turku University Hospital, Turku, Finland.
Jukka
J
Laine
Department of Pathology, University of Eastern Finland and Kuopio University Hospital, Kuopio, Finland.
Vesa
V
Kärjä
Department of Clinical Nutrition and Obesity Center, Kuopio University Hospital, Kuopio, Finland.
Jussi
J
Pihlajamäki
Department of Medicine, Turku University Hospital, Turku, Finland.
Lassi
L
Nelimarkka
Turku PET Centre, Turku, Finland; Department of Medicine, Turku University Hospital, Turku, Finland. Electronic address: pirjo.nuutila@utu.fi.
Pirjo
P
Nuutila
D000273:Adipose Tissue / Q000473:pathology; D000328:Adult; D050110:Bariatric Surgery; D003924:Diabetes Mellitus, Type 2 / Q000150:complications* / Q000378:metabolism*; D005260:Female; D005743:Gastrectomy / Q000379:methods; D015390:Gastric Bypass; D005947:Glucose / Q000378:metabolism*; D006801:Humans; D007333:Insulin Resistance; D008099:Liver / Q000378:metabolism* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009767:Obesity, Morbid / Q000150:complications / Q000378:metabolism* / Q000601:surgery*; D009929:Organ Size; D011446:Prospective Studies; D015431:Weight Loss
D005947:Glucose
(18)F-FDG; (18)F-fluorodeoxyglucose; BS; Bariatric surgery; Beta cell function; EGP; Endogenous glucose production; GLP-1; HGU; HbA(1c); Hepatic glucose uptake; IL-6; IL-8; Insulin clearance; LFC; Liver fat; MCP-1; MRI; MRS; OGTT; PET; RYGB; Roux-en-Y gastric bypass; SG; Sleeve gastrectomy; T2DM; VLCD; bariatric surgery; endogenous glucose production; glucagon-like peptide-1; glycosylated haemoglobin; hepatic glucose uptake; high-sensitivity C-reactive protein; hs-CRP; interleukin-6; interleukin-8; liver fat content; magnetic resonance imaging; magnetic resonance spectroscopy; monocyte chemotactic protein-1; oral glucose tolerance test; positron emission tomography; sleeve gastrectomy; type 2 diabetes; very-low-calorie diet