Insulin Therapy on Bone Macroscopic, Microarchitecture, and MechanicalProperties of Tibia in Diabetic Rats

Curr Diabetes Rev. 2024;20(9):e030124225214. doi: 10.2174/0115733998270859231117091741.

Abstract

Background: This study evaluated tibia's macroscopic structure, mechanical properties, and bone microarchitecture in rats with type 1 diabetes mellitus (T1DM).

Methods: Eighteen animals were divided into three groups (n=6): Non-diabetic (ND), diabetic (D), and diabetic+insulin (DI). T1DM was induced by streptozotocin; insulin was administered daily (4IU). The animals were euthanized 35 days after induction. The tibiae were removed and analyzed using macroscopic, micro-computed tomography (micro-CT) and three-point bending. The macroscopic analysis measured proximal-distal length (PD), antero-posterior thickness (AP) of proximal (AP-P) and distal (AP-D) epiphysis, and lateral-medial thickness (LM) of proximal (LM-P) and distal (LM-D) epiphysis. Micro-CT analysis closed porosity, tissue mineral density, and cortical thickness. The three-point bending test measured maximum strength, energy, and stiffness.

Results: The macroscopic analysis showed that D presented smaller measures of length and thickness (AP and AP-P) than ND and DI. More extensive measurements were observed of LM and AP-D thickness in DI than in D. In micro-CT, DI showed larger cortical thickness than D. Mechanical analysis showed lower strength in D than in other groups.

Conclusions: T1DM reduces bone growth and mechanical strength. Insulin therapy in diabetic rats improved bone growth and fracture resistance, making diabetic bone similar to normoglycemic animals.

Keywords: Diabetes mellitus; biomechanical phenomena; bone growth; insulin; micro-computed tomography.; tibia.

MeSH terms

  • Animals
  • Biomechanical Phenomena
  • Bone Density* / drug effects
  • Diabetes Mellitus, Experimental*
  • Diabetes Mellitus, Type 1* / complications
  • Diabetes Mellitus, Type 1* / drug therapy
  • Diabetes Mellitus, Type 1* / physiopathology
  • Hypoglycemic Agents* / therapeutic use
  • Insulin* / administration & dosage
  • Insulin* / therapeutic use
  • Male
  • Rats
  • Rats, Wistar
  • Tibia* / diagnostic imaging
  • Tibia* / drug effects
  • Tibia* / pathology
  • X-Ray Microtomography*

Substances

  • Insulin
  • Hypoglycemic Agents