Osteoporosis is the most important metabolic bone disease in patients with diabetes mellitus. Several studies have documented that Metformin ( Glucophage ) is osteogenic in vitro. In contrast, others showed no effect of Metformin on the osteogenic differentiation of bone marrow-derived mesenchymal stem cells. Incretin hormones have received much attention because of their beneficial effects beyond glycemia, including on bone health.
The study has evaluated the anti-osteoporotic effect of Metformin and Sitagliptin ( Januvia ) in postmenopausal diabetic women. Forty postmenopausal diabetic women were randomly divided into two equal groups.
Group 1 received Metformin ( 500 mg ) 1 tablet twice daily, and group 2 received Sitagliptin ( 100 mg ) 1 tablet/day, for 12 weeks.
Fasting blood and urine samples were collected for measurement of serum total alkaline phosphatase ( ALP ), osteocalcin, and urinary deoxypyridinoline ( DPD ).
Laboratory tests were measured at baseline, after 4 and 8 weeks, and at the end of the study.
Bone mineral density of the anterior posterior lumbar spine was measured by dual energy X-ray absorptiometry at baseline and after 12 weeks of the intervention.
In the Metformin-treated group, the mean values for all markers of bone turnover at 12 weeks of treatment were not significantly different from baseline.
In Sitagliptin-treated group 2, the mean serum total ALP was significantly decreased, serum osteocalcin levels were non-significantly decreased gradually by 10% at 12 weeks, while urinary DPD decreased significantly and was then maintained at 28% decrease at 12 weeks.
In conclusion, Metformin is neither osteogenic nor has anti-osteoporotic effect, while Sitagliptin could positively regulate bone metabolism. ( Xagena )
Hegazy SK, J Bone Miner Metab 2014; Epub ahead of print