Papers by Keyword: MMP-2

Abstract: To understand the effect of mechanical stimulation on posterior sclera reinforcement (PSR), the rabbit scleral fibroblasts after PSR were subjected to stretch in vitro and MMP-2 and TIMP-2 expression of scleral fibroblasts were evaluated. Three-week-old rabbits were monocularly performed by eyelid suturation randomly to prepare experimental myopia eye. After 60 days, the experimental myopia eyes were treated by PSR. After 6 months, the posterior pole scleral fibroblasts (normal sclera - group A, sclera after operation - group B and fusion region of sclera and reinforcing band group C) were isolated and cultured in vitro. The cells were subjected to cyclic stretch regimens (sine wave, 3% and 6% elongation amplitude, 0.1Hz, 48h duration) by FX-4000 Tension System. The MMP-2 and TIMP-2 expression of scleral fibroblasts were evaluated by ELISA method. The results show that after cyclic stretch to the scleral fibroblasts of the normal sclera and the sclera after operation, the MMP-2 expression was significantly reduced and the TIMP-2 expression was significantly increased, the MMP-2 and TIMP-2 expression of the scleral fibroblasts of the fusion region after operation was no changed. It was indicated that the mechanical stimulation could regulate the MMP-2 and TIMP-2 expression of scleral fibroblasts and play an important role in the process of treating high myopia with PSR surgery.

Abstract: This investigation is based on the premise that heavy metals are sequestered by the mineral phase of teeth [1,2], hydroxyapatite, during their formation and there is a relation between heavy metal pollution and progressive destruction of human primary tooth. Our study was carried out on temporary molars – sound and carious - extracted from children up to 6 year old, residing in an area of Romania known to be highly polluted with heavy metals (Pb and Cd). In carious dentin extracts we found increased levels of collagen type 1 and alkaline phosphatase activity that can be correlated with the remineralization processus during teeth decay. Gelatin zymography shown increased MMP-1 (type-I collagenase) and MMP-2 (gelatinase-A) activities only in dentin extract from carious teeth isolated from children residing in a highly polluted area, suggesting their role in pathological extracellular matrix (ECM) remodeling and degradation processes in the progression of carious decay.