Increased bone resorption may play a crucial role in the occurrence of osteopenia in patients with type 2 diabetes: Possible involvement of accelerated polyol pathway in its pathogenesis

• Published in: Diabetes research and clinical practice Vol. 82; no. 1; pp. 119 - 126
• Main Authors: Takizawa, Makoto, Suzuki, Kiyoshi, Matsubayashi, Tadashi, Kikuyama, Munetsugu, Suzuki, Haruhiko, Takahashi, Kazuto, Katsuta, Hidenori, Mitsuhashi, Junko, Nishida, Susumu, Yamaguchi, Shinya, Yoshimoto, Katsuhiko, Itagaki, Eiji, Ishida, Hitoshi
• Format: Journal Article
• Language: English
• Published: Ireland Elsevier Ireland Ltd 01.10.2008
• Subjects: Acid Phosphatase - blood; Bone Density; Bone Diseases, Metabolic - blood; Bone Diseases, Metabolic - etiology; Bone Diseases, Metabolic - metabolism; Bone resorption; Bone Resorption - blood; Diabetes Mellitus, Type 2 - blood; Diabetes Mellitus, Type 2 - complications; Diabetes Mellitus, Type 2 - metabolism; Diabetic osteopenia; Endocrinology & Metabolism; Humans; Isoenzymes - blood; L-Iditol 2-Dehydrogenase - metabolism; Male; Middle Aged; Osteoblasts; Osteocalcin - blood; Osteoclasts; Polymers - metabolism; Polyol pathway; Signal Transduction; Sorbitol - blood; Sorbitol - metabolism; Sorbitol - urine; Tartrate-Resistant Acid Phosphatase; Bone resorption; Osteoclasts; Diabetic osteopenia; Polyol pathway; Osteoblasts
• ISSN: 0168-8227; 1872-8227
• DOI: 10.1016/j.diabres.2008.07.008

Abstract In order to investigate the underlying mechanism of alterations in bone mineral metabolism in patients with type 2 diabetes, we determined circulating levels of bone functional markers along with urinary excretion of sorbitol (SOR) and bone mineral density (BMD), and also examined their mutual interrelationship. A total of 151 male type 2 diabetic patients were examined in this study. Forty-eight age-matched male healthy subjects were also studied as the controls. A significant reduction of serum intact osteocalcin (i-OC) was found in the diabetic groups ( p < 0.01). On the other hand, circulating levels of tartrate resistant acid phosphatase (TRAP) in the diabetic patients were significantly higher than those in the controls ( p < 0.01). Interestingly, a significantly negative relationship was observed between BMD and serum TRAP ( p < 0.01), although no significant relationship was noted between BMD and serum i-OC in diabetic patients. Urinary excretion of SOR was significantly elevated in the diabetic patients when compared with the controls ( p < 0.01). In addition, a significantly positive correlation was observed between serum TRAP and urinary SOR ( p < 0.01), but not between serum i-OC and urinary SOR. Elevated serum TRAP in diabetes was reduced after the administration of aldose reductase inhibitor ( p < 0.05). It seems most likely that the increase in osteoclastic function probably due to accelerated polyol pathway plays a crucial role in the pathogenesis of decreased bone mineral content in male patients with type 2 diabetes.