RESUMO
To study the effect of essential MCU regulator (EMRE) on myocardial ischemia injury in experimental mice with underlining mechanism. Methods: Myocardial EMRE expression was up-regulated by EMRE adenovirus (Ad-EMRE) injection in mice myocardium tissue. Our research included in 3 groups: Sham operation group, sham mice received myocardium injection of eGFP adenovirus (Ad-eGFP); Myocardial infarction (MI) control group, the mice received Ad-eGFP injection and 48 hours later had coronary LAD ligation to establish MI model; MI treatment group, MI mice received Ad-EMRE injection. All animals were treated in 3 weeks. Mice cardiac function was examined by ultrasound; cardiomyocyte hypertrophy was evaluated by wheat germ agglutinin (WGA) staining, collagen fibrosis was measured by Masson staining, cell apoptosis was determined by TUNEL assay, protein expressions of EMRE, caspase-3 and caspase-9 were detected by Western blot analysis and mitochondrial reactive oxygen species (ROS) was assayed by MitoSOX fluorescence probe. Results: Compared with MI control group, MI treatment group showed the worse cardiac function, aggravated cardiac hypertrophy and elevated collagen fibrosis; in addition, MI treatment group had obviously increased cardiomyocyte apoptosis and increased protein expressions of Caspase-3, Caspase-9 and more mitochondrial ROS production. Conclusion: Over expressed EMRE can increase mitochondrial ROS production, induce cardiomyocyte apoptosis and therefore, aggravate myocardial ischemia injury in experimental mice.
RESUMO
BACKGROUND:Mitochondrial calcium uptake 1 (MICU1) is one of the important molecules to maintain the mitochondrial calcium homeostasis. The regulation of MICU1 to mitochondrial calcium homeostasis may play an important role in diabetic cardiomyopathy, but the underlying mechanism remains unclear. OBJECTIVE:To construct a lentiviral vector carrying MICU1 gene to transfect H9C2 cel s, and then to assess MICU1 level in H9C2 cel s thereby establishing a platform for researching the occurrence and development of diabetic cardiomyopathy at a cel ular level. METHODS:DNA fragments of MICU1 were amplified by PCR, cleaved with Spe I, EcoR I and cloned into the lentiviral vector pRRLsin.CMV.eGFP to construct pRRLsin.CMV.MICU1-eGFP vector. 293T cel s were co-transfected with recombined pCMVDR8.91 and pCMV-VSVG to produce pRRLsin.CMV.MICU1-eGFP lentiviral viruses, and then used to infect H9C2 cel s. mRNA and protein expressions of MICU1 in the transfected H9C2 cel s were evaluated by real-time PCR and western blot assay. Mitochondrial calcium level in Rhod-2-stained H9C2 cel s was tested under confocal microscope. RESULTS AND CONCLUSION:The recombinant inducible lentiviral vector containing MICU1 gene was successful y constructed. 293T could express green fluorescent protein with increased MICU1 level after pRRLsin.CMV.MICU1-eGFP transfection. The mRNA and protein expressions of MICU1 in the infected H9C2 group were obviously up-regulated compared with the other groups. MICU1 could remarkably improve the mitochondrial calcium level under Rhod-2 staining. These results show that pRRLsin.CMV.MICU1-eGFP lentiviral viruses are efficient to transfect H9C2 cel s, which wil be powered to lay a foundation for the immortalized cel line establishment.