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Hyperhomocysteinemia decreases bone blood flow

Neetu Tyagi1, Thomas P Vacek, John T Fleming

  • 1Department of Physiology and Biophysics, School of Medicine, University of Louisville, KY, USA. n0tyag01@louisville.edu

Vascular Health and Risk Management
|February 23, 2011
PubMed

Insights

High homocysteine (Hcy) levels, or hyperhomocysteinemia, reduce bone blood flow and compromise bone strength. This study demonstrates Hcy

Area of Science:

  • Biomedical Science
  • Bone Biology
  • Metabolic Disease

Background:

  • Elevated plasma homocysteine (Hcy), termed hyperhomocysteinemia (HHcy), is linked to osteoporosis.
  • Reduced bone blood flow is a potential mechanism for impaired bone mechanical properties.

Purpose of the Study:

  • To investigate the hypothesis that HHcy decreases bone blood flow and biomechanical properties.
  • To determine the effect of Hcy on bone blood flow and related biochemical markers in a rat model.

Main Methods:

  • Male Sprague-Dawley rats were administered Hcy in drinking water for 8 weeks.
  • Measurements included plasma Hcy, vitamin B12, folate, systolic blood pressure, tibial blood flow, and tibial mass.
  • Laser Doppler flowmetry was used to assess tibial blood flow.

Main Results:

  • Hcy-treated rats exhibited significantly higher Hcy levels and lower vitamin B12 levels compared to controls.
  • Tibial blood flow was significantly reduced in Hcy-treated rats (0.51 ± 0.09 flow units) versus controls (0.78 ± 0.09 flow units).
  • Tibial mass was reduced in Hcy-treated rats, while bone density remained unchanged.

Conclusions:

  • Hcy significantly reduces bone blood flow in rats.
  • Reduced bone blood flow due to Hcy may contribute to compromised bone biomechanical properties.
  • This suggests a potential mechanism linking HHcy to osteoporosis.

Keywords:
bone densityhomocysteinetibia

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