"Dangerous duo": Chronic nicotine exposure intensifies diabetes mellitus-related deterioration in bone microstructure - An experimental study in rats

Life Sci. 2018 Nov 1:212:102-108. doi: 10.1016/j.lfs.2018.09.044. Epub 2018 Sep 25.

Abstract

Aims: Bony complications of diabetes mellitus (DM) are still insufficiently understood. Our aims were to analyze the individual and combined effects of chronic hyperglycemia and nicotine exposure on the femoral trabecular and cortical microarchitecture on a rat experimental model.

Main methods: The micro-computed tomography based bone microstructural evaluation was performed on male Wistar rats divided into four groups: control (n = 7), experimentally-induced DM (n = 8), chronically exposed to nicotine (n = 9) and the DM group exposed chronically to nicotine (n = 9).

Key findings: Chronic hyperglycemia caused mild trabecular deterioration; yet, the combination of hyperglycemia and nicotine exposure showed more deleterious effects on the trabecular bone. Namely, the DM + nicotine group had significantly lower bone volume fraction, fewer and more rod-like shaped trabeculae, along with higher trabecular separation and lower connectivity than the control group (p < 0.05). Nicotine alone did not show any significant deterioration compared to the control group. DM and DM + nicotine groups had lower cortical porosity than control and nicotine groups (p < 0.05). Cortical thickness did not show any significant intergroup differences, whereas bone perimeter and the mean polar moment of inertia were reduced in DM + nicotine group.

Significance: Mild effects of chronic hyperglycemia on bone structure were accentuated by the chronic nicotine exposure, although nicotine alone did not cause any significant bone changes. That suggests a synergistic effect of hyperglycemia and nicotine on bone deterioration and increased propensity to fracture. Indeed, better understanding of risk factors driving bone structural deterioration is a precondition to limit the complications associated with DM.

Keywords: Bone; Diabetes mellitus; Experimental model; Micro-CT; Nicotine.

MeSH terms

  • Animals
  • Bone Density / drug effects*
  • Bone Diseases / chemically induced
  • Bone Diseases / diagnostic imaging
  • Bone Diseases / pathology*
  • Cortical Bone / diagnostic imaging
  • Cortical Bone / drug effects
  • Cortical Bone / pathology*
  • Diabetes Complications / chemically induced
  • Diabetes Complications / diagnostic imaging
  • Diabetes Complications / pathology*
  • Diabetes Mellitus, Experimental / physiopathology*
  • Male
  • Nicotine / toxicity*
  • Nicotinic Agonists / toxicity
  • Rats
  • Rats, Wistar
  • X-Ray Microtomography / methods*

Substances

  • Nicotinic Agonists
  • Nicotine