Shozo Yano1,2, Toru Nabika2,3, Atsushi Nagai4,2, Tsuyoshi Hamano2,5, Masayuki Yamasaki2,6, Minoru Isomura2,3, Kuninori Shiwaku2,6, Shuhei Yamaguchi7, Toru Yamaguchi8, Toshitsugu Sugimoto8. 1. Department of Laboratory Medicine, Shimane University Faculty of Medicine, Shimane, Japan. Email: syano@med.shimane-u.ac.jp. 2. Shimane community-based health research and education (CoHRE), Shimane, Japan. 3. Department of Functional Pathology, Shimane University Faculty of Medicine, Shimane, Japan. 4. Department of Laboratory Medicine, Shimane University Faculty of Medicine, Shimane, Japan. 5. Organization for the Promotion of Project Research, Shimane University, Shimane, Japan. 6. Department of Environmental and Preventive Medicine, Shimane University Faculty of Medicine, Shimane, Japan. 7. Department of Internal Medicine 3, Shimane University Faculty of Medicine, Shimane, Japan. 8. Department of Internal Medicine 1, Shimane University Faculty of Medicine, Shimane, Japan.
Abstract
OBJECTIVE: Undercarboxylated osteocalcin (ucOC) produced from the bone was recently found to play a regulatory role in the insulin and adiponectin secretion. We performed a cross-sectional study to investigate the relationship between ucOC and diabetes mellitus (DM). METHODS: We included 1,870 subjects aged over 50 from participants of a health examination. According to the current medication and past history, 605 subjects had hypertension (HT), 316 had dyslipidemia (DL), and 182 had type 2 DM. Fasting blood samples were collected to measure concentrations of ucOC and the bone turnover marker, tartrate-resistant acid phosphatase 5b (TRACP5b) by ELISA. RESULTS: The serum ucOC level was significantly lower in DM(+) than DM(-) in both men and women. In a logistic regression analysis, a low level of ucOC was significantly associated with the presence of DM in both men and women after adjusting for age, BMI, serum creatinine, triglyceride, and TRACP5b. Multiple regression analysis showed a negative association of ucOC with HbA1c and fasting plasma glucose, and a positive association with the insulin level. In contrast, no association was found between TRACP5b and the indices above, suggesting that the effect of ucOC on the insulin secretion and the glycemic status was independent of bone turnover. CONCLUSIONS: The present cross-sectional study showed a significant association between ucOC and glucose metabolism after correction with bone turnover in a community-dwelling population both in men and women, indicating that ucOC may play an important role in the pathogenesis of DM through the pathways independent of bone metabolism.
OBJECTIVE: Undercarboxylated osteocalcin (ucOC) produced from the bone was recently found to play a regulatory role in the insulin and adiponectin secretion. We performed a cross-sectional study to investigate the relationship between ucOC and diabetes mellitus (DM). METHODS: We included 1,870 subjects aged over 50 from participants of a health examination. According to the current medication and past history, 605 subjects had hypertension (HT), 316 had dyslipidemia (DL), and 182 had type 2 DM. Fasting blood samples were collected to measure concentrations of ucOC and the bone turnover marker, tartrate-resistant acid phosphatase 5b (TRACP5b) by ELISA. RESULTS: The serum ucOC level was significantly lower in DM(+) than DM(-) in both men and women. In a logistic regression analysis, a low level of ucOC was significantly associated with the presence of DM in both men and women after adjusting for age, BMI, serum creatinine, triglyceride, and TRACP5b. Multiple regression analysis showed a negative association of ucOC with HbA1c and fasting plasma glucose, and a positive association with the insulin level. In contrast, no association was found between TRACP5b and the indices above, suggesting that the effect of ucOC on the insulin secretion and the glycemic status was independent of bone turnover. CONCLUSIONS: The present cross-sectional study showed a significant association between ucOC and glucose metabolism after correction with bone turnover in a community-dwelling population both in men and women, indicating that ucOC may play an important role in the pathogenesis of DM through the pathways independent of bone metabolism.