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Plasma Levels of Matrix Metalloprotease MMP-9 and Tissue Inhibitor TIMP-1 in Caucasian Patients with Polypoidal
Jakob Ø Sørensen1,2, Yousif Subhi1,2, Christopher R Molbech1,2
1Clinical Eye Research Division, Department of Ophthalmology, Zealand University Hospital, Vestermarksvej 23, DK-4000 Roskilde, Denmark.
Background:
Matrix metalloproteinase 9 (MMP-9) and tissue inhibitor of metalloproteinases 1 (TIMP-1) are regulating enzymes of the extracellular matrix. A systemic imbalance of MMP-9 and TIMP-1, thought to reflect an imbalance of the extracellular matrix homeostasis, is previously associated with polypoidal choroidal vasculopathy (PCV) in Asian patients. Previous studies suggest inter-ethnical differences in the genetic background and etiology of PCV. To further explore this issue, we studied the plasma levels of MMP-9 and TIMP-1 in Caucasian patients with PCV and compared to healthy age-matched controls.
Methods:
For this prospective case-control study, 60 participants were recruited who were either patients with PCV (n = 26) or healthy controls (n = 34). All participants underwent detailed clinical examination. We sampled fresh venous blood, isolated plasma, and quantified plasma concentrations of the extracellular matrix regulators MMP-9 and TIMP-1 using electrochemiluminescence immunoassays.
Results:
Plasma levels of MMP-9 (p = 0.4), TIMP-1 (p = 0.9), and MMP-9/TIMP-1 ratio (p = 0.4) did not differ significantly between patients with PCV and healthy controls. No differences appeared after adjusting for influencing co-variates in multivariate analyses.
Conclusion:
We demonstrate that Caucasian patients with PCV do not have altered levels of plasma MMP-9 or plasma TIMP-1. These findings suggest no strong evidence of a systemic imbalance of the extracellular matrix homeostasis in Caucasian patients with PCV. Our findings are in line with studies of other aspects of PCV that are also subject to significant inter-ethnical differences.
Insights
This study found no significant differences in plasma levels of matrix metalloproteinase 9 (MMP-9) or tissue inhibitor of metalloproteinases 1 (TIMP-1) in Caucasian patients with polypoidal choroidal vasculopathy (PCV). These findings suggest no systemic extracellular matrix imbalance in this patient group.
Area of Science:
- Ophthalmology
- Biochemistry
- Genetics
Background:
- Matrix metalloproteinase 9 (MMP-9) and tissue inhibitor of metalloproteinases 1 (TIMP-1) regulate extracellular matrix homeostasis.
- Systemic imbalances of MMP-9 and TIMP-1 are linked to polypoidal choroidal vasculopathy (PCV) in Asian populations.
- Inter-ethnic variations in PCV etiology suggest distinct pathophysiological mechanisms.
Purpose of the Study:
- To investigate plasma levels of MMP-9 and TIMP-1 in Caucasian patients with PCV.
- To compare these levels with those in healthy Caucasian controls.
- To assess potential systemic extracellular matrix imbalances in Caucasian PCV patients.
Main Methods:
- Prospective case-control study involving 60 participants (26 PCV patients, 34 controls).
- Detailed clinical examinations were performed on all participants.
- Plasma concentrations of MMP-9 and TIMP-1 were quantified using electrochemiluminescence immunoassays.
Main Results:
- No significant differences were observed in plasma MMP-9 levels between PCV patients and controls (p=0.4).
- No significant differences were observed in plasma TIMP-1 levels between PCV patients and controls (p=0.9).
- The MMP-9/TIMP-1 ratio also did not differ significantly between the groups (p=0.4), even after multivariate analysis.
Conclusions:
- Caucasian patients with PCV do not exhibit altered plasma levels of MMP-9 or TIMP-1.
- These results indicate a lack of strong evidence for systemic extracellular matrix homeostasis imbalance in Caucasian PCV.
- Findings align with known inter-ethnic differences in PCV pathogenesis and clinical presentation.
