BACKGROUND: We have previously reported that matrix metalloproteinase-2 (MMP-2) contributes to myocardial ischemia-reperfusion injury by degradation of troponin I, a regulatory element of the contractile proteins. MMP activities are also tightly regulated by tissue inhibitors of metalloproteinase (TIMPs). The change in TIMPs during acute myocardial ischemia-reperfusion injury is not clear. METHODS AND RESULTS: Isolated rat hearts were perfused either aerobically for 75 minutes or subjected to 15, 20, or 25 minutes of global, no-flow ischemia followed by 30 minutes of aerobic reperfusion. During reperfusion after ischemia, there was a rapid, enhanced release of TIMP-4, the most abundant TIMP in the heart, into the coronary effluent, as shown both by reverse zymography and Western blot. There was a negative correlation between the recovery of cardiac mechanical function and the release of TIMP-4 during reperfusion in hearts subjected to different durations of ischemia. Immunogold electron microscopy revealed a close association of TIMP-4 with the sarcomeres in aerobically perfused hearts. Moreover, TIMP-4 was present only in thin myofilaments prepared from aerobically perfused hearts but not in ischemic-reperfused hearts. An enhanced MMP activity was shown in ischemic-reperfused hearts by in situ zymography. CONCLUSIONS: Loss of TIMP-4 from the cardiac myocyte leads to an increase in net myocardial MMP activity that contributes to acute myocardial stunning injury.
BACKGROUND: We have previously reported that matrix metalloproteinase-2 (MMP-2) contributes to myocardial ischemia-reperfusion injury by degradation of troponin I, a regulatory element of the contractile proteins. MMP activities are also tightly regulated by tissue inhibitors of metalloproteinase (TIMPs). The change in TIMPs during acute myocardial ischemia-reperfusion injury is not clear. METHODS AND RESULTS: Isolated rat hearts were perfused either aerobically for 75 minutes or subjected to 15, 20, or 25 minutes of global, no-flow ischemia followed by 30 minutes of aerobic reperfusion. During reperfusion after ischemia, there was a rapid, enhanced release of TIMP-4, the most abundant TIMP in the heart, into the coronary effluent, as shown both by reverse zymography and Western blot. There was a negative correlation between the recovery of cardiac mechanical function and the release of TIMP-4 during reperfusion in hearts subjected to different durations of ischemia. Immunogold electron microscopy revealed a close association of TIMP-4 with the sarcomeres in aerobically perfused hearts. Moreover, TIMP-4 was present only in thin myofilaments prepared from aerobically perfused hearts but not in ischemic-reperfused hearts. An enhanced MMP activity was shown in ischemic-reperfused hearts by in situ zymography. CONCLUSIONS: Loss of TIMP-4 from the cardiac myocyte leads to an increase in net myocardial MMP activity that contributes to acute myocardial stunning injury.
Authors: Jiqiu Chen; Ching-Hsuan Tung; Jennifer R Allport; Si Chen; Ralph Weissleder; Paul L Huang Journal: Circulation Date: 2005-04-04 Impact factor: 29.690
Authors: N Yaras; M Sariahmetoglu; A Bilginoglu; A Aydemir-Koksoy; A Onay-Besikci; B Turan; R Schulz Journal: Br J Pharmacol Date: 2008-09-22 Impact factor: 8.739
Authors: Mehrnoosh Saghizadeh; Andrei A Kramerov; Jian Tajbakhsh; Annette M Aoki; Charles Wang; Ning-Ning Chai; Julia Y Ljubimova; Takako Sasaki; Gabriel Sosne; Marc R J Carlson; Stanley F Nelson; Alexander V Ljubimov Journal: Invest Ophthalmol Vis Sci Date: 2005-10 Impact factor: 4.799