Spermine inhibits expression of Fas/FasL in simulated ischemia-reperfusion-injured cardiomyocytes of neonatal rat / 中国病理生理杂志

ABSTRACT

AIM: To explore the effects and possible mechanism of exogenous spermine on the apoptosis of primary cultured neonatal cardiomyocytes induced by simulated ischemia-reperfusion (I/R) injury. METHODS: To establish a model of simulated I/R, the primary cultured neonatal rat cardiomyocytes were incubated in ischemia-mimetic solution (under the conditions of hypoxia plus serum deprivation) for 2 h, and re-incubated the cells in normal culture medium for 24 h. The apoptotic cell death was assayed by flow cytometry. The morphological alterations of the cells were observed under transmission electron microscope. The transcription and expression of Fas and FasL were determined by the methods of RT-PCR, Western blotting and immunofluorescence. RESULTS: The cells exposed to I/R underwent significant apoptosis, and the percentage of apoptotic cells was 27.4%±1.8%, much higher than that in normal group (5.7%±0.3%). In I/R group the evident histopathological changes were observed and the myocardial transcription and expression of Fas and FasL were significantly upregulated. Compared to normal group, mRNA expression of Fas and FasL increased 2.2 folds and 2.4 folds, respectively, and their proteins increased 1.7 folds and 1.9 folds at 24 h of reperfusion respectively (P<0.01). Pretreatment with 10 μmol/L spermine significantly inhibited apoptosis of I/R injured cells, and the percentage of apoptotic cells was 21.7%±1.3% (P<0.01, as compared to I/P group). Spermine also suppressed the expression of Fas and FasL significantly (P<0.05 or P<0.01, as compared to I/P group). CONCLUSION: Spermine plays anti-apoptotic effect on the cultured neonatal myocardial cells under the condition of I/R injury by suppressing the expression of Fas/FasL.