Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: UMLS:C0851184 (
thinning
)
11,252
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Our aim was to observe the effects of psychological stress on the structure of the temporomandibular joint (TMJ), and to evaluate the expression of matrix
metallopeptidase
-3 (MMP-3) and tissue inhibitor of metalloproteinase-3 (TIMP-3) in condylar chondrocytes in rats. The rats were divided into 3 groups of 12 according to the duration of psychological stress: 3 weeks or 6 weeks, and 6 weeks of recovery. A fourth group of 12 rats was used as controls. Each rat was evaluated by the open-field test and the weight measured. The results confirmed psychological stress in 24 of the 36 rats (67%). The tissues of the TMJ were stained with haematoxylin and eosin and pathological changes were studied under a light microscope. MMP-3 and TIMP-3 expression was investigated using the SP kit. The experimental groups showed
thinning
of articular cartilage, shedding of collagen fibres, cracks in the articular discs, and other structural changes that were aggravated with time, from three weeks to six weeks. The 6-week recovery group showed an improvement in these changes, which indicated the initiation of joint repair. The MMP-3 expression rate correlated with the degree of joint lesion, while the TIMP-3 rate showed an opposite trend and was highest in the 6-week recovery group. Our findings clearly indicate that psychological stress may play an important part in the development of TMJ diseases in rats; further studies should be made to extrapolate the results to other models before clinical use.
...
PMID:Effect of psychological stress on the structure of the temporomandibular joint and the expression of MMP-3 and TIMP-3 in the cartilage in rats. 2506 Sep 74
Myopia is a serious sight-compromising condition in which decreases in scleral biomechanical strength are associated with protease up-regulation resulting in
thinning
of its collagenous framework and changes in the extracellular matrix composition. Matrix
metallopeptidase
(MMP)-2 is one of the known proteases mediating these alterations. To determine whether MMP-2 up-regulation precedes myopia development, the direct effects of gain and loss in Mmp2 gene function were evaluated on refractive development and form deprivation myopia in mice. Four weeks after injecting an adeno-associated virus serotype 8 packaged Mmp2 overexpression vector (AAV8-Mmp2), scleral MMP-2 up-regulation was accompanied by significant myopia in a normal visual environment. In contrast, AAV8 packaging with shRNA targeting Mmp2 inhibited rises in MMP-2 expression induced by form deprivation by 54% and reduced myopia development by 23% compared with eyes injected with an irrelevant scrambled sequence. Because opposing changes in MMP-2 protein expression levels had corresponding effects on myopia progression, up-regulation of this protease contributes to inducing this condition. This notion of a cause-and-effect relationship between MMP-2 up-regulation and myopia development is supported by showing that form-deprived myopia development was attenuated by 27% in fibroblast-specific Mmp2 deletion (S100a4
cre
Mmp2
fl/fl
) mice relative to Cre-negative littermates (Mmp2
fl/fl
). Therefore, MMP-2 is a potential drug target for inhibiting myopia progression.
...
PMID:Cause and Effect Relationship between Changes in Scleral Matrix Metallopeptidase-2 Expression and Myopia Development in Mice. 2980 30
