BACKGROUND: Cyclo-oxygenase-2 (COX-2) is induced in cardiomyocytes only in response to stress, such as ischaemia. OBJECTIVE: To assess COX-2 expression at the site of recent myocardial infarction. METHODS: COX-2 expression was evaluated by specific immunostaining in cardiomyocytes from 23 subjects who died 10-60 days after acute myocardial infarction. The relation between COX-2 myocardial expression and apoptotic rate was investigated. Cardiomyocyte apoptotic rate was defined as the number of cells co-expressing in situ end labelling of DNA fragmentation (TUNEL) and immunostaining for activated caspase-3. RESULTS: COX-2 expression was found in cardiomyocytes at the site of infarction in nine of 23 cases (39%). It was associated with fivefold higher apoptotic rates (median 17.9% (interquartile range 11.0-25.4%) v 3.7% (0.6-12.8%); p = 0.016), and apoptotic rate increased progressively from mild to intense COX-2 staining (p for trend 0.009). COX-2 expression co-localised with TUNEL nuclear staining in myocytes, and there was a high concordance between COX-2 and hypoxia induced factor 1-alpha staining (78%, p = 0.021) and between COX-2 and bax (83%, p = 0.014). Subjects showing myocardial COX-2 expression were more likely to have enlarged hearts (p = 0.050), and intense COX-2 staining was strictly associated with symptomatic heart failure (p = 0.035). CONCLUSIONS: COX-2 is expressed in cardiomyocytes in nearly 40% of cases at the site of recent acute myocardial infarction, even late after the index event. Its expression was associated with extremely high apoptotic rates. These findings suggest a potential cause-effect link between COX-2 expression and enhanced myocardial apoptosis in ischaemic cardiomyopathy.
BACKGROUND: Cyclo-oxygenase-2 (COX-2) is induced in cardiomyocytes only in response to stress, such as ischaemia. OBJECTIVE: To assess COX-2 expression at the site of recent myocardial infarction. METHODS: COX-2 expression was evaluated by specific immunostaining in cardiomyocytes from 23 subjects who died 10-60 days after acute myocardial infarction. The relation between COX-2 myocardial expression and apoptotic rate was investigated. Cardiomyocyte apoptotic rate was defined as the number of cells co-expressing in situ end labelling of DNA fragmentation (TUNEL) and immunostaining for activated caspase-3. RESULTS: COX-2 expression was found in cardiomyocytes at the site of infarction in nine of 23 cases (39%). It was associated with fivefold higher apoptotic rates (median 17.9% (interquartile range 11.0-25.4%) v 3.7% (0.6-12.8%); p = 0.016), and apoptotic rate increased progressively from mild to intense COX-2 staining (p for trend 0.009). COX-2 expression co-localised with TUNEL nuclear staining in myocytes, and there was a high concordance between COX-2 and hypoxia induced factor 1-alpha staining (78%, p = 0.021) and between COX-2 and bax (83%, p = 0.014). Subjects showing myocardial COX-2 expression were more likely to have enlarged hearts (p = 0.050), and intense COX-2 staining was strictly associated with symptomatic heart failure (p = 0.035). CONCLUSIONS: COX-2 is expressed in cardiomyocytes in nearly 40% of cases at the site of recent acute myocardial infarction, even late after the index event. Its expression was associated with extremely high apoptotic rates. These findings suggest a potential cause-effect link between COX-2 expression and enhanced myocardial apoptosis in ischaemic cardiomyopathy.
Authors: S Govoni; E Masoero; L Favalli; A Rozza; R Scelsi; S Viappiani; C Buccellati; A Sala; G Folco Journal: Neurosci Lett Date: 2001-05-04 Impact factor: 3.046
Authors: K Shinmura; X L Tang; Y Wang; Y T Xuan; S Q Liu; H Takano; A Bhatnagar; R Bolli Journal: Proc Natl Acad Sci U S A Date: 2000-08-29 Impact factor: 11.205
Authors: Jae Hyung Kim; Lukasz J Bugaj; Young Jun Oh; Trinity J Bivalacqua; Sungwoo Ryoo; Kevin G Soucy; Lakshmi Santhanam; Alanah Webb; Andre Camara; Gautam Sikka; Daniel Nyhan; Artin A Shoukas; Monica Ilies; David W Christianson; Hunter C Champion; Dan E Berkowitz Journal: J Appl Physiol (1985) Date: 2009-08-06
Authors: D Santini; A Abbate; S Scarpa; F Vasaturo; G G Biondi-Zoccai; R Bussani; F De Giorgio; F Bassan; D Camilot; M P Di Marino; F Feroce; F Baldi; F Silvestri; F Crea; A Baldi Journal: J Clin Pathol Date: 2004-12 Impact factor: 3.411