The deleterious effect of bariatric surgery on cortical and trabecular bone density in the femurs of non-obese, type 2 diabetic Goto-Kakizaki rats.
BACKGROUND
The effects of type 2 diabetes on bone mass and microstructure are not clear. The aim of this study was to evaluate bone microstructural properties and volumetric bone mineral density (vBMD) in type 2 diabetic Goto-Kakizaki non-obese rats after gastrojejunal bypass and their relationship with hormonal parameters.


METHODS
We designed an experimental study in Goto-Kakizaki rats with and without gastrojejunal bypass, performing densitometric and microstructural studies of the distal femur using X-ray computed microtomography (micro-CT). Levels of insulin, glucagon, leptin, and glucagon-like peptide-1 (GLP-1) were also determined.


RESULTS
We observed reduced cortical (1,488.92 ± 98.2 vs. 1,727.92 ± 133.45 mg/cm(3), p = 0.028) and trabecular (180.8 ± 9 vs. 261.23 ± 45.54 mg/cm(3), p = 0.036) vBMD in operated rats. Bone volume fraction (BV/TV) and trabecular connectivity were reduced in operated rats, while there was a reduction in cortical thickness and an increase in rod-like trabeculae at the expense of plate-like trabeculae. Leptin was reduced (1,042 ± 549 vs. 2,447 ± 1,035 pg/ml, p = 0.05) and GLP-1 increased (1.62 ± 0.32 vs. 0.96 ± 0.1 ng/ml, p = 0.008) but only leptin showed a significant association with vBMD CONCLUSIONS: In type 2 diabetic Goto-Kakizaki rats, gastrojejunal bypass produces a reduction in cortical and trabecular bone mineral density and a deterioration in bone quality that could be explained, in part, by the reduction in leptin levels.
Institute of Endocrinology, Rio Hortega University Hospital, C/Dulzaina 2, 47016, Valladolid, Spain. castrv@terra.es
José Luis
JL
Pérez-Castrillón
José Antonio
JA
Riancho
Daniel
D
de Luis
José Ramón
JR
Caeiro
David
D
Guede
Manuel
M
González-Sagrado
Marta
M
Ruiz-Mambrilla
María
M
Domingo-Andrés
Rosa
R
Conde
David
D
Primo-Martín
D000818:Animals; D050110:Bariatric Surgery / Q000009:adverse effects; D015415:Biomarkers / Q000378:metabolism; D001696:Biomechanical Phenomena; D015519:Bone Density; D003924:Diabetes Mellitus, Type 2 / Q000378:metabolism*; D005269:Femur / Q000000981:diagnostic imaging / Q000378:metabolism*; D020738:Leptin / Q000378:metabolism*; D008297:Male; D051381:Rats; D015203:Reproducibility of Results; D055114:X-Ray Microtomography
D015415:Biomarkers; D020738:Leptin