Parathyroid Hormone (1-34) Improves Bone Mineral Density and Glucose Metabolism in Spontaneously Diabetic Torii-Leprfa Rats

The Spontaneously Diabetic Torii-Lepr(fa) (SDT-fa/fa) rat, a model of obese type 2 diabetes, shows obesity, hyperglycaemia and low bone mineral density (BMD). The objective of this study is to evaluate the effects of parathyroid hormone (1-34) [PTH(1-34)] on BMD and glucose metabolism in the SDT-fa/fa rat. SDT-fa/fa rats showed obesity with hyperglycaemia and decreased serum osteocalcin levels and the tibial BMD. A 4-week treatment of PTH(1-34) (20 µg/kg/day) increased the serum osteocalcin levels and the tibial BMD, and decreased the serum glucose levels without changing the serum insulin levels. These findings indicate that PTH(1-34) improved not only BMD but also glucose metabolism in SDT-fa/fa rats. This study suggests that PTH(1-34) is a novel agent for the treatment of diabetic osteoporosis.