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: EC:3.4.24.3 (
collagenase
)
18,340
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
We studied the presence of collagen degrading enzymes (matrix metalloproteinases, MMPs) in porcine myocardium following ischemia and late reperfusion. In nine pigs, left anterior descending coronary artery was occluded for 6 h followed by reperfusion for 3 h. Six pigs without
coronary occlusion
served as controls. After the reperfusion period, transmural biopsies from the anterior (ischemic zone) and posterior wall (non-ischemic myocardium) in the left ventricle were obtained and extracted. Heparin-Sepharose isolated components in extracts were analysed for
collagenase
(triple-helical collagen degradation) and gelatinase activity (zymography). Immunohistochemistry using anti-human (
MMP-1
, MMP-2, MMP-9, and fibronectin) antibodies was performed on additional biopsies. Collagenase (
MMP-1
) and gelatinases (MMP-2, MMP-9) could be demonstrated in the extracts of non-ischemic myocardium from ischemic/reperfused as well as control pigs and
MMP-1
and MMP-9 activity was found to be increased in ischemic/reperfused myocardium compared with non-ischemic myocardium. In ischemic/reperfused myocardium from live pigs investigated, myocyte necrosis could be confirmed by fibronectin immunoreaction in myocytes and
MMP-1
and MMP-9 immunoreactions were increased. MMP-9 was present in cells likely to be infiltrating leukocytes in a patchy distribution throughout the ischemic myocardium. Quite coincident with MMP-9 positive cells,
MMP-1
immunoreaction appeared in necrotic myocytes, in addition to reactions observed in vessel walls, endo- and epicardium, and extracellular matrix in non-ischemic myocardium. Thus, the results showed increased amounts of
collagenase
(
MMP-1
) and gelatinase (MMP-9) in ischemic/ reperfused myocardium, indicating the appearance of increased amounts of collagen degrading enzymes very early following ischemia and late reperfusion.
...
PMID:Increased amounts of collagenase and gelatinase in porcine myocardium following ischemia and reperfusion. 971 Aug 10
The plasma fibrinolytic/proteolytic balance was assessed in 60 stable angina patients who underwent control coronary catheterization and the results were correlated with angiographic findings and control samples (n = 20). The concentrations of t-PA, PAI-1,
collagenase
(
MMP-1
), tissue inhibitor of MMP (TIMP-1), plasmin-antiplasmin (PAP) complexes and alpha2-macroglobulin (alpha2-M) were measured in plasma samples. The results showed a significant increase of PAP (p <0.001) and a reduction of alpha2-M (p <0.001) in the group of patients when compared to controls, indicating a degree of fibrinolysis/proteolysis activation. There was no correlation between the different parameters analyzed and the extent of angiographically proven atherosclerosis (one or more stenotic vessels), while the t-PA levels were significantly elevated (p <0.03) in patients with coronary stenosis > or =75% or occlusion. We conclude that there is a disturbance of the plasma fibrinolysis/proteolysis in patients with stable angina not related to the extent of atherosclerosis. The t-PA levels may be a good marker for
coronary occlusion
in these patients.
...
PMID:Fibrinolysis/proteolysis balance in stable angina pectoris in relation to angiographic findings. 1152 15
Granulocyte-colony stimulating factor (G-CSF) has been reported to mobilize bone marrow multi-potent stem cells, which differentiate into cardiac myocytes after myocardial infarction (MI). However, there have not been any reports regarding the effect of G-CSF on stem cell infiltration in the MI site. Hearts of mice that had undergone
coronary occlusion
were isolated and digested with
collagenase
. Infiltrating cells in the heart were collected using Percoll density gradients. The infiltrating cells were sorted for side population (SP) cells using Hoechst 33342 dye. Hundreds of infiltrating SP cells were found in the heart from 1 to 14 d after MI. There were only a few SP cells in hearts without infarction. Infiltrating SP cells were increased in the 4-d G-CSF treated group compared with the vehicle group (1106 +/- 106 vs. 323 +/- 26/heart, P < 0.05). The infiltration of inflammatory cells was not influenced by the G-CSF treatment. In a separate series of experiments, we confirmed that the infiltrating SP cells were derived from bone marrow. That is, SP cells in the infarcted hearts of mice, which had been transplanted with bone marrow from ROSA 26 (beta-galactosidase transgenic) mice, were positive for beta-galactosidase. In the immunohistochemical examination, Sca-1(+)/CD45(-) cells were existed in the infarcted site after MI. Therefore, SP cells may infiltrate into infarcted heart. G-CSF augmented this kind of stem cell infiltration without increasing inflammatory cells. These results suggest that G-CSF may enhance myocardial regeneration without aggravated inflammation in the infarcted heart.
...
PMID:G-CSF treatment increases side population cell infiltration after myocardial infarction in mice. 1513 66
We investigated the effect of cardiac-targeting erythropoietin (EPO)-encapsulated liposomes with sialyl Lewis(X) (SLX) on myocardial infarct (MI) size, left ventricular (LV) remodeling and function, and its molecular mechanism for repairing infarcted myocardium. In rabbits, MI was induced by 30 min of
coronary occlusion
followed by reperfusion. EPO-encapsulated liposomes with SLX (L-EPO group), EPO-encapsulated liposomes without SLX (L-EPO without SLX group), liposomes with SLX without EPO (L group), or saline (saline group) were intravenously administered immediately after MI. MI sizes and numbers of microvessels were assessed 14 days after MI. Prosurvival proteins and signals were assessed by Western blot analysis 2 and 14 days after MI. Confocal microscopy and electron microscopy showed the specific accumulation of liposomes with SLX in the infarcted myocardium. MI and cardiac fibrosis areas were significantly smaller in the L-EPO group than in the other groups. LV function and remodeling were improved in the L-EPO group. The number of CD31-positive microvessels was significantly greater in the L-EPO group than in the other groups. Higher expressions of EPO receptors, phosphorylated (p)Akt, pERK, pStat3, VEGF, Bcl-2, and promatrix
metalloproteinase-1
were observed in the infarct area in the L-EPO group than in the other groups. EPO-encapsulated liposomes with SLX selectively accumulated in the infarct area, reduced MI size, and improved LV remodeling and function through activation of prosurvival signals and by exerting antifibrotic and angiogenic effects. EPO-encapsulated liposomes with SLX may be a promising strategy for active targeting treatment of acute MI.
...
PMID:Postinfarct active cardiac-targeted delivery of erythropoietin by liposomes with sialyl Lewis X repairs infarcted myocardium in rabbits. 2341 61
Hemorrhage is recognized as a new independent predictor of adverse outcomes following acute myocardial infarction. However, the mechanisms of its effects are less understood. The aim of our study was to probe the downstream impact of hemorrhage towards chronic remodeling, including inflammation, vasodilator function and matrix alterations in an experimental model of hemorrhage. Myocardial hemorrhage was induced in the porcine heart by intracoronary injection of
collagenase
. Animals (N = 18) were subjected to
coronary occlusion
followed by reperfusion in three groups (six/group): 8 min ischemia with hemorrhage (+HEM), 45 min infarction with no hemorrhage (I - HEM) and 45 min infarction with hemorrhage (I + HEM). MRI was performed up to 4 weeks after intervention. Cardiac function, edema (T
2
, T
1
), hemorrhage (T
2
*), vasodilator function (T
2
BOLD), infarction and microvascular obstruction (MVO) and partition coefficient (pre- and post-contrast T
1
) were computed. Hemorrhage was induced only in the +HEM and I + HEM groups on Day 1 (low T
2
* values). Infarct size was the greatest in the I + HEM group, while the +HEM group showed no observable infarct. MVO was seen only in the I + HEM group, with a 40% occurrence rate. Function was compromised and ventricular volume was enlarged only in the hemorrhage groups and not in the ischemia-alone group. In the infarct zone, edema and matrix expansion were the greatest in the I + HEM group. In the remote myocardium, T
2
elevation and matrix expansion associated with a transient vasodilator dysfunction were observed in the hemorrhage groups but not in the ischemia-alone group. Our study demonstrates that the introduction of myocardial hemorrhage at reperfusion results in greater myocardial damage, upregulated inflammation, chronic adverse remodeling and remote myocardial alterations beyond the effects of the initial ischemic insult. A systematic understanding of the consequences of hemorrhage will potentially aid in the identification of novel therapeutics for high-risk patients progressing towards heart failure.
...
PMID:Hemorrhage promotes chronic adverse remodeling in acute myocardial infarction: a T
1
, T
2
and BOLD study. 3287 32
