Background: Matrix metalloproteinase 9 (MMP-9), also known as 92 kDa type IV collagenase, 92 kDa gelatinase or gelatinase B (GELB), is a matrix in, a class of enzymes that belong to the zinc metalloproteinases family involved in the degradation of the extracellular matrix. Gelatinase B or 92 kDa type IV collagenase, also known as matrix metalloproteinase-9 (MMP- 9) plays an important role in the pathogenesis of hypertension. The present study was designed to evaluate whether fasting homocysteine is associated with essential hypertension by causing alterations in the endothelial biomarkers.

Methods: A total of 525 subjects between the age group of 20-55 years of age, from both sexes who were attending the Hypertensive clinic in Sri Ramachandra Medical College were enrolled for the study. They were grouped as three-Group I being controls, Group II hypertensives without omorbities and Group III hypertensive with end organ damage . After overnight fasting, blood and spoturine samples were collected. All the biochemical parameters were estimated by standard methodologies. The plasmahomocysteine was determined by ELISA method (Axis Shield, UK), MMP-9 was determined by ELISA Method (R&D SYSTEMS, Minneapolis, USA)

Results: The results are expressed as Mean±SD. The MMP-9 mean levels were found to be 100 ± 99, 155 ± 29 and 219 ± 27 (in pg/mL) in groups I, II and III respectively.

Conclusion: The activation of these MMPs may be generated by vascular cell adhesion protein (VCAM-1) and intercellular adhesion molecule (ICAM-1) being up regulated in hyperhomocysteinemia leading to increased monocyte and leukocyte binding

Keywords: Essential hypertension, mmp-9, homocysteine, extracellular matrix.

1. Wang J, Tsirka SE. "Neuroprotection by inhibition of matrix metalloproteinases in a mouse model of intracerebral haemorrhage." Brain. 2005;128 (7): 1622–33.
2. Van; Vandooren, J; den Steen, PE; Opdenakker, G.. "Biochemistry and molecular biology of gelatinase B or matrix metalloproteinase-9 (MMP-9) The next decade". Crit Rev Biochem Mol Biol.2013;48 (3): 222–72.
3. Van; den Steen, PE; Dubois, B; Nelissen, I; Rudd, PM; Dwek, RA; Opdenakker, G. "Biochemistry and molecular biology of gelatinase B or matrix metalloproteinase-9 (MMP-9)". Crit Rev Biochem Mol Biol. 2002;37 (6): 375–536.
4. Genersch, E., Hayess, K., Neuenfeld, Y.,and Haller, H.Sustained ERK Phosphorylation is Necessary but not sufficient for MMP-9 Regulation in Endothelial Cells. J. Cell Sci. 2000;113: 4319–330.
5. Whatling C, McPheat W, Hurt-Camejo E.Matrix Management. Assigning Different Roles for MMP-2 and MMP-9 in Vascular Remodeling. Arterioscler Thromb VascBiol. 2004;24:10–11.
6. Derosa G., D'Angelo A., Ciccarelli L. Matrix Metalloproteinase-2, -9, and Tissue Inhibitor of Metalloproteinase-1 in Patients with Hypertension. Endothelium. 2006;13:227–31.
7. Yasmin Wallace S., Mceniery C.M., Dakham, Z. Matrix Metalloproteinase-9 ( MMP-9) , MMP-2, and Serum Elastase Activity are Associated with Systolic Hypertension and Arterial Stiffness. Arterioscler Thromb Vasc Biol. 2005;25:372-78.
8. Tayebjee M.H., Nadar S.K., Mac Fadyen R.J. Tissue inhibitor of MMP-1 and MMP-9 levels in patients with hypertension. Relationship to tissue Doppler indices of diastolic relaxation. AJH. 2004; 17 :770–74.
9. Weber KT, Pick R, Jalil JE, Janicki JS, Carroll EP. Patterns of myocardial fibrosis. J Mol Cell Cardiol. 1989;21 (5):121–31.
10. Lehoux S, Lemarie CA, Esposito B, Lijnen HR, Tedgui A. Pressure-induced matrix metalloproteinase-9 contributes to early hypertensive remodeling. Circulation. 2004;109:1041–47.
11. Katholi RE, Couri DM. Left ventricular hypertrophy: major risk factor in patients with hypertension: update and practical clinical applications. Intl J Hypertens. 2011; 495349 .
12. Li H, Simon H, Bocan TM, Peterson JT. MMP/TIMP expression in spontaneously hypertensive heart failure rats: the effect of ACE- and MMP inhibition. Cardiovasc Res.2000; 46: 298–306.
13. Ahmed SH, Clark LL, Pennington WR, Webb CS, Bonnema DD, Leonardi AH, et al. Matrix metalloproteinases/tissue inhibitors of metalloproteinases: relationship between changes in proteolytic determinants of matrix composition and structural, functional, and clinical manifestations of hypertensive heart disease. Circulation. 2006;113: 2089–96.
14. Silverman MD, Ramapogal JT, Davis M, Lopez G, Rosenbaum JT, Lelkes PI. Homocysteine Upregulates Vascular Cell Adhesion Molecule1 Expression in Cultured Human Aortic Endothelial Cells and Enhances Monocyte Adhesion. Arteriosclerosis Thromb Vasc Biol. 2002;22:587–
15. Deem TL, Cook-Mills JM.Vascular Cell Adhesion Molecule-1 (VCAM-1) Activation of Endothelial Cell Matrix Metalloproteinases. Blood. 2004; 104: 2385–

Dr R. S. Hermes

Associate Professor, Department of Biochemistry, FAHS, Aarupadai Veedu Medical College & Hospitals, Puducherry