Department of Biophysics, Mersin University, Faculty of Medicine, TR-33169 Mersin, Turkey.
Diabetes Res Clin Pract. 2012 Sep;97(3):461-7. doi: 10.1016/j.diabres.2012.03.005. Epub 2012 Apr 6.
To investigate the effect of insulin therapy on biomechanical properties of bone in streptozotocin (STZ)-induced type 1 diabetes mellitus (T1DM) in rats.
A total of 28 male Wistar-Albino rats (12-week-old; 210-300g) were divided into 4 groups (n=7 for each) including control [C; no treatment], sham [Sh; distilled water i.p., for 8 weeks], diabetes [T1DM; 65mg/kg of STZ, single i.p.] and diabetes+insulin treatment [T1DM+I; 65mg/kg of STZ, single i.p.+insulin; 2-4UI/day/rat, i.p., for 8 weeks] groups. Body weight, blood glucose levels (BGLs), bone mineral density (BMD) and geometric/mechanical properties of bone tissue were evaluated.
BGLs in diabetic rats were significantly increased compared to non-diabetic rats, while the body weights were decreased (p<0.05). Femur length and cross-sectional area of femur were significantly decreased in both T1DM and T1DM+I groups (p<0.05). The significant reduction obtained in BMD in T1DM rats compared with C and Sh (p<0.05) groups was reversed by insulin treatment (p<0.05). Displacement, absorbed energy, maximum load, ultimate stress and toughness were significantly decreased inT1DM and T1DM+I groups compared to C and Sh groups (p<0.05).
In conclusion, insulin treatment seems to be ineffective in restoration of biomechanical deterioration of bone specific to STZ-induced T1DM.
研究胰岛素治疗对链脲佐菌素（STZ）诱导的 1 型糖尿病（T1DM）大鼠骨生物力学特性的影响。
将 28 只雄性 Wistar-Albino 大鼠（12 周龄；210-300g）分为 4 组（每组 7 只），包括对照组[C；无治疗]、假手术组[Sh；腹腔内注射蒸馏水，8 周]、糖尿病组[T1DM；65mg/kg 的 STZ，单次腹腔内注射]和糖尿病+胰岛素治疗组[T1DM+I；65mg/kg 的 STZ，单次腹腔内注射+胰岛素；2-4UI/天/只，8 周]。评估体重、血糖水平（BGL）、骨密度（BMD）和骨组织的几何/力学特性。
与非糖尿病大鼠相比，糖尿病大鼠的 BGL 显著升高，而体重降低（p<0.05）。T1DM 和 T1DM+I 组的股骨长度和股骨横截面积均显著降低（p<0.05）。与 C 和 Sh 组相比，T1DM 组的 BMD 显著降低（p<0.05），而胰岛素治疗则逆转了这一情况（p<0.05）。与 C 和 Sh 组相比，T1DM 和 T1DM+I 组的位移、吸收能量、最大载荷、极限应力和韧性均显著降低（p<0.05）。
总之，胰岛素治疗似乎对 STZ 诱导的 T1DM 特异性骨生物力学恶化的恢复无效。
