Tissue Inhibitor of Metalloproteinase-3 Ameliorates Diabetes-Induced Retinal Inflammation

Purpose: Endogenous tissue inhibitor of matrix metalloproteinase-3 (TIMP-3) has powerful regulatory effects on inflammation and angiogenesis. In this study, we investigated the role of TIMP-3 in regulating inflammation in the diabetic retina.Methods: Vitreous samples from patients with proliferative diabetic retinopathy (PDR) and non-diabetic patients were subjected to Western blot analysis. Streptozotocin-treated rats were used as a preclinical diabetic retinopathy (DR) model. Blood-retinal barrier (BRB) breakdown was assessed with fluorescein isothiocyanate (FITC)-conjugated dextran. Rat retinas, human retinal microvascular endothelial cells (HRMECs) and human retinal Müller glial cells were studied by Western blot analysis and ELISA. Adherence of human monocytes to HRMECs was assessed and in vitro angiogenesis assays were performed.Results: Tissue inhibitor of matrix metalloproteinase-3 in vitreous samples was largely glycosylated. Intravitreal injection of TIMP-3 attenuated diabetes-induced BRB breakdown. This effect was associated with downregulation of diabetes-induced upregulation of the p65 subunit of NF-κB, intercellular adhesion molecule-1 (ICAM-1), and vascular endothelial growth factor (VEGF), whereas phospho-ERK1/2 levels were not altered. In Müller cell cultures, TIMP-3 significantly attenuated VEGF upregulation induced by high-glucose (HG), the hypoxia mimetic agent cobalt chloride (CoCl2) and TNF-α and attenuated MCP-1 upregulation induced by CoCl2 and TNF-α, but not by HG. TIMP-3 attenuated HG-induced upregulation of phospho-ERK1/2, caspase-3 and the mature form of ADAM17, but not the levels of the p65 subunit of NF-κB and the proform of ADAM17 in Müller cells. TIMP-3 significantly downregulated TNF-α-induced upregulation of ICAM-1 and VCAM-1 in HRMECs. Accordingly, TIMP-3 significantly decreased spontaneous and TNF-α- and VEGF-induced adherence of monocytes to HRMECs. Finally, TIMP-3 significantly attenuated VEGF-induced migration, chemotaxis and proliferation of HRMECs.Conclusion:In vitro and in vivo data point to anti-inflammatory and anti-angiogenic effects of TIMP-3 and support further studies for its applications in the treatment of DR.

Some indicators of left ventricular dysfunction in hypertensive patients, depending on the level of matrix metalloproteinases and tissue inhibitors of metalloproteinase-1

Aim. To study the level of matrix metalloproteinases-1 and -2, and tissue inhibitor of metalloproteinases-1, the indicator of left ventricular myocardial deformation in patients with stage 12 hypertension. Methods. 114 patients (40 women and 74 men) with hypertension of 12 stages observed in the cardiology Department of the Road clinical hospital Chita II were examined. The median age was 428.3 years. Left ventriclular diastolic function was studied by using tissue Doppler imaging in apical four-chamber views. Serum matrix metalloproteinase-1, matrix metalloproteinase-2, and tissue inhibitor of metalloproteinases-1 levels were measured in all patients on automated immunoassay analyzers using ready-to-use ELISA kits. Results. An increase in serum levels of matrix metalloproteinases-1 and -2 in the group of patients with hypertension and diastolic dysfunction by 46 and 47%, respectively, was found against increased levels of serum tissue inhibitor of metalloproteinase-1 (р=0.049). In patients with diastole dysfunction, myocardial global longitudinal strain was decreased in was observed by 22.8% compared with patients without diastole dysfunction (p 0.05). The analysis revealed a moderate negative relationship between left ventricular global longitudinal strain and the serum levels of metalloproteinases-2 (r=0.64, p 0.05). Conclusion. In patients with hypertension and left ventricular diastolic dysfunction, a decrease in left ventricular global longitudinal strain is associated with the serum level of matrix metalloproteinase-2; a tissue inhibitor of metalloproteinases-1 is unrelated to left ventricular global myocardial strain.

Serum tissue inhibitor of MMP-1 levels at any moment of the first week of spontaneous intracerebral hemorrhage may predict early mortality

Aim: To determine whether serum levels of MMP-9 and tissue inhibitor of matrix metalloproteinases (TIMP)-1 during the first week after spontaneous intracerebral hemorrhage (SIH) could be used for mortality prediction. Materials & methods: We included 117 patients with severe supratentorial SIH (defined as Glasgow Coma Scale <9). We determined serum concentrations of MMP-9 and TIMP-1 at days 1, 4 and 8 of severe SIH diagnosis. Results: The area under curve of serum TIMP-1 concentrations at days 1, 4 and 8 to predict 30-day mortality of 75% (p < 0.001), 82% (p < 0.001) and 73% (p < 0.001). Conclusion: Thus, the novel findings of our study were that serum levels of TIMP-1 during the first week of SIH may be used for mortality prediction.