Matrix metalloproteinase (MMP-2, -9) and tissue inhibitor (TIMP-1, -2) activity in tear samples of pediatric type 1 diabetic patients

Abstract

Significant correlations between TIMP-2 and HB(A1C) and between Schirmer test results and HB(A1C) were revealed. Significant increase in tear MMP and TIMP levels in pediatric type 1 diabetic patients may be suggestive of disease progression and localized pathologic remodelling. Further studies are required in order to ascertain whether MMPs and TIMPs could be employed as indicators of early disease progression.

Human tear proteomics and peptidomics in ophthalmology: Toward the translation of proteomic biomarkers into clinical practice

“…They have found a strong correlation between MMP-9 concentrations and clinical parameters(76). The overexpression of this protein has been also validated in several other diseases including keratoconjunctivitis, keratoconus, diabetes mellitus, and conjunctivochalasis(77)(78)(79)(80)(81). All these studies demonstrate the lack of specificity of MMP-9 for the diagnosis of a specific ocular surface disease but corroborate the efficacy of the protein in the prediction of inflammatory alterations.…”

Functional Activity of Matrix Metalloproteinases 2 and 9 in Tears of Patients With Glaucoma

“…Similar results of tear cytokines signature profiles indicating disease have been reported in diabetic retinopathy and animal models of Sjögren's syndrome. 20,21 The MMPs also have been implicated in postoperative fibrosis after filtering surgeries and after antiglaucoma therapy. 6 It is unclear if the increased MMP activity in tears seen in our study represents actual MMP-9 upregulation in tears as a part of general inflammatory pathway activation in glaucomatous eyes or is a result of progressive leeching from the ocular surface tissues, like conjunctiva.…”

Alteration of the bone tissue material properties in type 1 diabetes mellitus: A Fourier transform infrared microspectroscopy study

“…These modifications cannot be explained by the augmented collagen glycation but rather by enzymatic degradation of matrix collagen. Interestingly, further reports have been made regarding higher matrix metalloproteinase (MMP) activities, mainly MMP-2, MMP-8, MMP-9, MMP-13 and MMP-14, in connective tissues, other than bone, in type 1 diabetes [38][39][40][41][42]. To the best of our knowledge, MMP activities have never been assessed in bone tissue of diabetic animals.…”