Bone marrow transplantation improves endothelial function in hypertensive Dahl salt-sensitive rats

J Am Soc Hypertens. Sep-Oct 2012;6(5):331-7. doi: 10.1016/j.jash.2012.08.003.

Abstract

Bone marrow-derived endothelial progenitor cells (EPCs) constitute an important endogenous system in the maintenance of endothelial integrity and vascular homeostasis. Cardiovascular risk factors are associated with a reduced number and functional capacity of EPCs. Here we investigated the effect of transplantation of bone marrow-derived cells from Dahl salt-resistant rat into age-matched Dahl salt-sensitive (DS) rat on blood pressure, endothelial function, and circulating EPC number. The recipient DS rats were fed a normal (0.5% NaCl, NS) or high-salt (4% NaCl, HS) diet for 6 weeks after bone marrow transplantation (BMT). DS rats on a NS or a HS diet without BMT were used as controls. Hypertensive DS (HS-DS) rat (systolic blood pressure: 213 ± 4 mm Hg vs. 152 ± 4 mm Hg in NS, P < .05) manifested impaired endothelium-dependent relaxation to acetylcholine (EDR), increased gene expression of vascular oxidative stress and proinflamamtory cytokines, and decreased eNOS expression. BMT on HS-DS rat significantly improved EDR and eNOS expression, reduced oxidative stress without reduction in SBP (206 ± 6 mm Hg). Flow cytometry analysis showed that there was no difference in the number of circulating EPCs, demonstrated by expression of EPC markers CD34, cKit, and vascular endothelial growth factor, between hypertensive and normotensive rats. Surprisingly, BMT resulted in a 5- to 10-fold increase in the previously mentioned EPC markers in hypertensive, but not normotensive rat. These results suggest that DS rat has an impaired ability to increase bone marrow-derived EPCs in response to HS diet challenge, which may contribute to endothelial dysfunction.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acetylcholine / pharmacology
  • Animals
  • Blood Pressure / drug effects
  • Bone Marrow Transplantation / methods*
  • Cell Count / methods
  • Cytokines / metabolism
  • Endothelial Cells* / drug effects
  • Endothelial Cells* / metabolism
  • Endothelium, Vascular* / drug effects
  • Endothelium, Vascular* / metabolism
  • Endothelium, Vascular* / physiopathology
  • Flow Cytometry
  • Hypertension* / metabolism
  • Hypertension* / physiopathology
  • Models, Animal
  • Nitric Oxide Synthase Type III / metabolism
  • Oxidative Stress / drug effects
  • Rats
  • Rats, Inbred Dahl
  • Sodium Chloride, Dietary / pharmacology*
  • Stem Cells / physiology
  • Vascular Endothelial Growth Factor A / metabolism
  • Vasodilation / drug effects

Substances

  • Cytokines
  • Sodium Chloride, Dietary
  • Vascular Endothelial Growth Factor A
  • NOS3 protein, human
  • Nitric Oxide Synthase Type III
  • Acetylcholine