Effect of Roux-en-Y gastric bypass and diet-induced weight loss on diabetic kidney disease in the Zucker diabetic fatty rat.
BACKGROUND
Reductions in urinary protein excretion after Roux-en-Y gastric bypass (RYGB) surgery in patients with diabetic kidney disease have been reported in multiple studies.


OBJECTIVE
To determine the weight loss dependence of the effect of RYGB on urinary protein excretion by comparing renal outcomes in Zucker diabetic fatty rats undergoing either gastric bypass surgery or a sham operation with or without weight matching.


METHODS
University laboratories.


METHODS
Zucker diabetic fatty rats underwent surgery at 18 weeks of age. A subgroup of sham operated rats were weight matched to RYGB operated rats by restricting food intake. Urinary protein excretion was assessed at baseline and at postoperative weeks 4 and 12. Renal histology and macrophage-associated inflammation were assessed at postoperative week 12.


RESULTS
Progressive urinary protein excretion was attenuated by both RYGB and diet-induced weight loss, albeit to a lesser extent by the latter. Both weight loss interventions produced equivalent reductions in glomerulomegaly, glomerulosclerosis, and evidence of renal macrophage infiltration.


CONCLUSIONS
Weight loss per se improves renal structure and attenuates renal inflammatory responses in an experimental animal model of diabetic kidney disease. Better glycemic control post-RYGB may in part explain the greater reductions in urinary protein excretion after gastric bypass surgery.
Diabetes Complications Research Centre, Conway Institute, School of Medicine, University College Dublin, Dublin, Ireland.
Karl J
KJ
Neff
Diabetes Complications Research Centre, Conway Institute, School of Medicine, University College Dublin, Dublin, Ireland; Department of Surgery, Trinity Centre for Health Sciences, St. James's Hospital, Dublin, Ireland.
Jessie A
JA
Elliott
Institute of Veterinary Physiology, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland; Department of Surgery, University of Wurzburg, Wurzburg, Germany.
Caroline
C
Corteville
Institute of Veterinary Physiology, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland; Zurich Center for Integrative Human Physiology, University of Zurich, Zurich, Switzerland.
Kathrin
K
Abegg
Bariatric Surgery, Clinica Las Condes, Santiago, Chile.
Camilo
C
Boza
Institute of Veterinary Physiology, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland; Zurich Center for Integrative Human Physiology, University of Zurich, Zurich, Switzerland.
Thomas A
TA
Lutz
Diabetes Complications Research Centre, Conway Institute, School of Medicine, University College Dublin, Dublin, Ireland. Electronic address: neil.docherty@ucd.ie.
Neil G
NG
Docherty
Diabetes Complications Research Centre, Conway Institute, School of Medicine, University College Dublin, Dublin, Ireland; Gastrosurgical Laboratory, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
Carel W
CW
le Roux
D000818:Animals; D003921:Diabetes Mellitus, Experimental / Q000628:therapy; D003928:Diabetic Nephropathies / Q000628:therapy*; D004038:Diet, Reducing; D015390:Gastric Bypass; D006984:Hypertrophy / Q000628:therapy; D007678:Kidney Glomerulus / Q000473:pathology; D008264:Macrophages / Q000502:physiology; D008297:Male; D009393:Nephritis / Q000628:therapy; D011507:Proteinuria / Q000209:etiology; D011897:Random Allocation; D011924:Rats, Zucker; D012598:Sclerosis / Q000628:therapy; D015431:Weight Loss / Q000502:physiology*
Bariatric; Diabetic kidney disease; Gastric bypass; RYGB; Renal inflammation; Urinary protein excretion; Weight loss; Zucker diabetic fatty rat