Femoral bone structure in Otsuka Long-Evans Tokushima Fatty rats

Abstract

ObjectivesType 2 diabetes mellitus (T2DM) increases fracture risk despite normal to high levels of bone mineral density. Bone quality is known to affect bone fragility in T2DM. The aim of this study was to clarify the trabecular bone microstructure and cortical bone geometry of the femur in T2DM model rats.MethodsFive-week-old Otsuka Long-Evans Tokushima Fatty (OLETF; n = 5) and Long-Evans Tokushima Otsuka (LETO; n = 5) rats were used. At the age of 18 months, femurs were scanned with micro-computed tomography, and trabecular bone microstructure and cortical bone geometry were analyzed.ResultsTrabecular bone microstructure and cortical bone geometry deteriorated in the femur in OLETF rats. Compared with in LETO rats, in OLETF rats, bone volume fraction, trabecular number and connectivity density decreased, and trabecular space significantly increased. Moreover, in OLETF rats, cortical bone volume and section area decreased, and medullary volume significantly increased.ConclusionsLong-term T2DM leaded to deterioration in trabecular and cortical bone structure. Therefore, OLETF rats may serve as a useful animal model for investigating the relationship between T2DM and bone quality.

High-fat/high-sucrose diet results in higher bone mass in aged rats

“…The procedures for analyses of TBA and CBG were performed according to the micro-CT guidelines for assessment of rodent bone microstructure ( Bouxsein et al, 2010 ), as previously reported by our group ( Minematsu et al, 2016a , Minematsu et al, 2016b , Minematsu et al, 2017 ). The bilateral femurs and tibias were dissected out, and then soft tissues were removed.…”

“…Therefore, excess sucrose intake, by which high blood glucose is induced, appears to attenuate bone formation via bone metabolism disturbance and/or malfunction of osteoblasts and eventually lose bone mass. Actually, we have recently reported that bone properties, including bone mass, TBA/CBG parameters and bone mechanical strength, deteriorate in the femur/tibia of diabetic Otsuka Long-Evans Tokushima Fatty rats with high blood glucose and high HbA1c values ( Minematsu et al, 2016b , Minematsu et al, 2017 ). In view of these facts, HFS diet-induced trabecular/cortical bone mass increase, reported herein and by Lavet et al, might have been ascribable to high fat content rather than high sucrose content in the diet; in other words, high fat content in the HFS diet might have hidden the deleterious action of sucrose on bone health.…”

Effect of Obesity on Bone Metabolism

“…Причому споживання раціону з високим вмістом жиру та/або сахарози впливає на метаболізм кісткової тканини у молодих гризунів, проте у старих гризунів цей процес все ще недостатньо вивчений. Відзначили, що надлишкове споживання сахарози саме по собі призводило до гальмування утворення кістки через порушення її метаболізму та/ або активності остеобластів і, як наслідок, до втрати кісткової маси, мінеральної щільності і механічної міцності [78,79]. Тому збільшення маси кістки, яке спостерігали [77] після споживання дієти з високим вмістом жирів і сахарози ймовірно пояснюється якраз високим вмістом жиру, а не сахарози.…”