This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Tanus-Santos, J. E. Articles by Gerlach, R. F. Search for Related Content PubMed PubMed Citation Articles by Tanus-Santos, J. E. Articles by Gerlach, R. F.

(Arteriosclerosis, Thrombosis, and Vascular Biology. 2005;25:e127.)
© 2005 American Heart Association, Inc.

Letter to the Editor

Circulating Matrix Metalloproteinase-9 Levels as a Possible Marker of Aortic Stiffness

Jose E. Tanus-Santos; Raquel F. Gerlach

Department of Pharmacology, Faculty of Medicine of Ribeirao Preto, University of Sao Paulo, Brazil

To the Editor,

Yasmin et al have recently reported very interesting findings showing that large artery stiffness has important effects on the cardiovascular risk.¹ They have found increased serum matrix metalloproteinase (MMP)-9 levels in subjects with isolated systolic hypertension compared with healthy subjects. In addition, they have found that serum MMP-9 levels can predict aortic stiffness.¹ However, a major limitation to the conclusions derived from their MMP-9 measurements is that artificially higher MMP-9 concentrations are found in serum samples compared with plasma samples.^2–5 Importantly, although a high correlation exists between MMP-9 levels in plasma separated from blood drawn into tubes with different anticoagulants, no correlation was found between MMP-9 levels in serum and in plasma. In summary, preanalytical conditions and other methodological issues⁶ are of major importance when assessing MMPs in clinical samples.

References

1. Yasmin, Wallace S, McEniery CM, Dakham Z, Pusalkar P, Maki-Petaja K, Ashby MJ, Cockcroft JR, Wilkinson IB. Matrix metalloproteinase-9 (MMP-9), MMP-2, and serum elastase activity are associated with systolic hypertension and arterial stiffness. Arterioscler Thromb Vasc Biol. 2005; 25: 372–378.[Abstract/Free Full Text]
2. Jung K, Lein M, Laube C, Lichtinghagen R. Blood specimen collection methods influence the concentration and the diagnostic validity of matrix metalloproteinase 9 in blood. Clin Chim Acta. 2001; 314: 241–244.[CrossRef][Medline] [Order article via Infotrieve]
3. Jung K, Laube C, Lein M, Lichtinghagen R, Tschesche H, Schnorr D, Loening SA. Kind of sample as preanalytical determinant of matrix metalloproteinase 2 and 9 and tissue inhibitor of metalloproteinase 2 in blood. Clin Chem. 1998; 44: 1060–1062.[Free Full Text]
4. Gerlach RF, Uzuelli JA, Souza-Tarla CD, Tanus-Santos JE. Effect of anticoagulants on plasma matrix metalloproteinase (MMP)-2 and MMP-9 activities. Anal Biochem. In Press.
5. Makowski GS, Ramsby ML. Use of citrate to minimize neutrophil matrix metalloproteinase-9 in human plasma. Anal Biochem. 2003; 322: 283–286.[CrossRef][Medline] [Order article via Infotrieve]
6. Souza-Tarla CD, Uzuelli JA, Machado AA, Gerlach RF, Tanus-Santos JE. Methodological issues affecting the determination of plasma matrix metalloproteinase (MMP)-2 and MMP-9 activities. Clin Biochem. 2005; 38: 410–414.[CrossRef][Medline] [Order article via Infotrieve]

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Tanus-Santos, J. E. Articles by Gerlach, R. F. Search for Related Content PubMed PubMed Citation Articles by Tanus-Santos, J. E. Articles by Gerlach, R. F.