Effects of chronic lead exposure on bone mineral properties in femurs of growing rats

Toxicology. 2017 Feb 15:377:64-72. doi: 10.1016/j.tox.2016.11.017. Epub 2016 Nov 30.

Abstract

Lead exposure has been associated with several defective skeletal growth processes and bone mineral alterations. The aim of the present study is to make a more detailed description of the toxic effects of lead intoxication on bone intrinsic material properties as mineral composition, morphology and microstructural characteristics. For this purpose, Wistar rats were exposed (n=12) to 1000ppm lead acetate in drinking water for 90days while control group (n=8) were treated with sodium acetate. Femurs were examined using inductively coupled plasma optical emission spectrometry (ICP-OES), Attenuated Total Reflection Fourier transform infrared spectroscopy (ATR-FTIR), X-ray diffraction (XRD), and micro-Computed Tomography (μCT). Results showed that femur from the lead-exposed rats had higher carbonate content in bone mineral and (Ca2++Mg2++ Na+)/P ratio values, although no variations were observed in crystal maturity and crystallite size. From morphological analyses, lead exposure rats showed a decreased in trabecular bone surface and distribution while trabecular thickness and cortical area increased. These overall effects indicate a similar mechanism of bone maturation normally associated to age-related processes. These responses are correlated with the adverse actions induced by lead on the processes regulating bone turnover mechanism. This information may explain the osteoporosis diseases associated to lead intoxication as well as the risk of fracture observed in populations exposed to this toxicant.

Keywords: Bone mineralization; Bone morphology; Bone turnover; Lead intoxication; Osteoporosis; Rat femur.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Bone Density / drug effects*
  • Bone Density / physiology
  • Bone Remodeling / drug effects*
  • Bone Remodeling / physiology
  • Female
  • Femur / drug effects*
  • Femur / growth & development*
  • Femur / metabolism
  • Lead / administration & dosage*
  • Lead / toxicity*
  • Random Allocation
  • Rats
  • Rats, Wistar
  • Spectroscopy, Fourier Transform Infrared
  • X-Ray Diffraction

Substances

  • Lead