|
|
Blood, 15 July 2007, Vol. 110, No. 2, pp. 762-769.
Prepublished online as a Blood First Edition Paper on March 29, 2007; DOI 10.1182/blood-2006-12-063602.
 Previous Article | Next Article 
Submitted December 19, 2006
Accepted March 26, 2007
Enhanced erythro-phagocytosis in polycythemic mice overexpressing erythropoietin
Anna Bogdanova, Deyan Mihov, Hans Lutz, Bianca Saam, Max Gassmann, and Johannes Vogel*
Institute of Veterinary Physiology, Vetsuisse Faculty and Zurich Center for Integrative Human Physiology (ZIHP), University of Zurich, Zurich, Switzerland
Institute of Biochemistry, ETH Zurich, Zurich, Switzerland
* Corresponding author; email: jvogel{at}vetphys.uzh.ch.
Adaptive mechanisms to hematocrit levels of 0.9 in our erythropoietin overexpressing mice (tg6) include increased plasma nitric oxide levels and erythrocyte flexibility. Doubled reticulocyte counts in tg6 suggest an increased erythrocyte turnover. Here we show that compared to wild type (wt) animals, erythrocyte lifespan in tg6 is 70% lower in tg6 mice. Transgenic mice have a younger erythrocyte population as indicated by higher intercellular water and potassium content, higher flexibility, decreased density, increased surface to volume ratio and decreased osmotic fragility. Interestingly, despite being younger, the tg6 erythrocyte population also harbors characteristics of accelerated aging such as an increased band 4.1a to 4.1b ratio, signs of oxidative stress or decreased surface CD47 and sialic acids. In tg6 in vivo tracking of PKH26-labeled erythrocytes revealed dramatically increased erythrocyte incorporation by their liver macrophages. In vitro experiments showed that tg6 macrophages are more active than wt macrophages and that tg6 erythrocytes are more attractive for macrophages than wt ones. In conclusion, in tg6 mice erythrocyte ageing is accelerated, which results, together with an increased number and activity of their macrophages, in enhanced erythrocyte clearance. Our data points towards a new mechanism down-regulating red cell mass in excessive erythrocytosis in mice.
 CiteULike  Connotea  Del.icio.us  Digg  Reddit  Technorati What's this?
This article has been cited by other articles:
|
|
|
|
 
M. Gassmann, A. Manini, T. Stallmach, B. Saam, G. Kuhn, B. Grenacher, A. Y. Bogdanova, and J. Vogel
Abortion in Mice with Excessive Erythrocytosis Is Due to Impaired Arteriogenesis of the Uterine Arcade
Biol Reprod,
June 1, 2008;
78(6):
1049 - 1057.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
J. Soliz, C. Soulage, D. M. Hermann, and M. Gassmann
Acute and chronic exposure to hypoxia alters ventilatory pattern but not minute ventilation of mice overexpressing erythropoietin
Am J Physiol Regulatory Integrative Comp Physiol,
October 1, 2007;
293(4):
R1702 - R1710.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
