ABSTRACT
Background and Objectives@#Acute myocardial infarction (AMI) often occurs suddenly and leads to fatal consequences. Ferroptosis is closely related to the progression of AMI.However, the specific mechanism of ferroptosis in AMI remains unclear. @*Methods@#We constructed a cell model of AMI using AC16 cells under oxygen and glucose deprivation (OGD) conditions and a mice model of AMI using the left anterior descending (LAD) ligation. The 3-(4, 5-dimethylthiazol-2-yl)-2, 5 diphenyltetrazolium bromide was employed to determine cell viability. The levels of lactate dehydrogenase, creatine kinase, reactive oxygen species (ROS), glutathione (GSH), malondialdehyde (MDA), and iron were measured using corresponding kits. Dual luciferase reporter gene assay, RNAbinding protein immunoprecipitation, and RNA pull-down were performed to validate the correlations among AC005332.7, miR-331-3p, and cyclin D2 (CCND2). Hematoxylin and eosin staining was employed to evaluate myocardial damage. @*Results@#AC005332.7 and CCND2 were lowly expressed, while miR-331-3p was highly expressed in vivo and in vitro models of AMI. AC005332.7 sufficiency reduced ROS, MDA, iron, and ACSL4 while boosting the GSH and GPX4, indicating that AC005332.7 sufficiency impeded ferroptosis to improve cardiomyocyte injury in AMI. Mechanistically, AC005332.7 interacted with miR-331-3p, and miR-331-3p targeted CCND2. Additionally, miR-331-3p overexpression or CCND2 depletion abolished the suppressive impact of AC005332.7 on ferroptosis in OGD-induced AC16 cells. Moreover, AC005332.7 overexpression suppressed ferroptosis in mice models of AMI. @*Conclusions@#AC005332.7 suppressed ferroptosis in OGD-induced AC16 cells and LAD ligation-operated mice through modulating miR-331-3p/CCND2 axis, thereby mitigating the cardiomyocyte injury in AMI, which proposed novel targets for AMI treatment.
ABSTRACT
Objective:To construct the postgraduate teaching case database of rotation in department of cardiology, and to explore its application effect.Methods:The postgraduate teaching case base of rotation in department of cardiology was constructed during April 2020 to December 2020. A total of 32 graduate students rotating in Department of Cardiology of Affiliated Hospital of Guilin Medical University from January 2021 to April 2021 were selected and randomly divided into two groups. The routine group adopted the traditional teaching method, and the research group applied the teaching case base on this basis, both for one month. The examination results, the changes of clinical practice ability before and after the teaching, and the satisfaction with the teaching mode were compared between the two groups. SPSS 22.0 was used for t test and chi-square test. Results:The final results of the theoretical examination and practical operation examination of the two groups were higher than those of the entrance examination ( P<0.05), and the results of the theoretical examination and practical operation examination of the research group were higher than those of the routine group ( P<0.05). The scores of clinical practice ability of inquiry, case analysis, diagnosis, treatment and follow-up in the two groups after teaching were higher than those before teaching ( P<0.05), and the scores of clinical practice ability in the research group after teaching were higher than those in the routine group ( P<0.05). The satisfaction scores on improving examination results, enhancing clinical practice ability, deepening professional understanding and enhancing professional confidence of the teaching mode of the research group were higher than those of the routine group ( P<0.05). Conclusion:The construction and application of postgraduate teaching case base of cardiology rotation can improve the examination results, enhance the clinical practice ability, and achieve the satisfaction of postgraduates.
ABSTRACT
Objective To investigate the relationship of serum levels of homocysteine, cystain C and uric acid with ca?rotid atherosclerosis in H-type hypertension patients. Methods A total of 132 H-type hypertension patients were collected to be studied. Their carotid intima-media thickness (IMT) was measured by Doppler ultrasonography. And according to the result of carotid artery atherosclerosis, all patients were divided into normal cIMT group (n=40),thickened cIMT group (n=43) and plague formation group (n=49). Their serum Hcy, Cyst-C, UA, blood glucose, blood lipid, blood urea nitrogen and se?rum creatinine were compared among three group and their relationship with cIMT were analyzed. Logistic regression was used to screen risk factors for carotid atherosclerosis. Results There was no significant difference in serum levels of blood glucose,blood urea nitrogen, creatinine, serum creatinine (Scr), triglyceride (TG), total cholesterol (TC), low density lipppro?tein cholesterol (LDL-c) among these three groups (P>0.05). The level of high-density lipoprotein (HDL-c) in thickened cIMT group was higher than that in plague formation group, and lower than normal cIMT group, while both serum levels of Cyst-c and UA were lower in thickened cIMT group than those in plague formation group but higher than those in normal cIMT group (P<0.05). In addition, serum level of Hcy in normal cIMT group was higher than that in thickened cIMT group and plague formation group. The cIMT grade was positively correlated with serum levels of Hcy, Cyst-C and UA (r=0.26, 0.30, 0.23, P<0.05), but was negative correlated with HDL-c(r=-0.38, P<0.05). Further more, Logistic regression analy?sis showed that Hcy,Cyst-C and UA were independent risk factors for cIMT. Conclusion Serum levels of Hcy, Cyst-C and UA are closely related to the cIMT,which indicates that they are independent risk factors of cIMT and may be used as mark?ers in judging the developments and preventions of arteriosclerosis.
ABSTRACT
Objective To investigate the dynamic changes of cardiomyocyte apoptosis and Caspase-12 activation after coronary microembolization (CME) in rats. Methods The CME models were produced by injection of 42 μm microspheres (3000/0.1 ml) into the left ventricle during clampinduced ascending aorta occlusion for 10 seconds in adult male Sprague-Dawley rats (CME group).The sham-operation group was injected with saline instead (S group). The survivors were randomly divided into five groups: 3 h, 6 h, 12 h, 24 h and 4 weeks (n=10, each), respectively. In addition,10 rats were designed as normal control group. Cardiomyocyte apoptosis was detected by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) staining. The expressions of Caspase-3, 12 and procaspase-3 and 12 were detected with Western-blot analysis. The activity of Caspase-12 was determined with fluorometric assay kit. Results (1)Compared with the shamoperation group and normal control group, the apoptosis rates of cardiomyocytes in CME group were significantly increased at each time point respectively (all P＜0.05). Apoptotic cardiomyocytes were found mainly in the border zones and infarct foci. The apoptosis rates of cardiomyocytes at 3 h, 6 h,12 h, 24 h and 4 weeks after CME were (1.76±0.68)%, (3.17±1.26)%, (1.34±0.12)%,(1.07±0.65)% and (0.30±0.13)%, respectively. The apoptosis rates of cardiomyocytes increased at 3 h after CME, peaked at 6 h after CME (all P＜0.05), and then gradually decreased with lowest value at 4 weeks (all P＜0.01). (2)Compared with sham-operation group and normal control group,the relative activation level of Caspase-3 and 12 in CME group increased remarkably (all P＜0.05).The time courses of Caspase-3 and 12 expressions corresponded well to those of cardiomyocyte apoptosis after CME. Conclusions The amount of cardiomyocytes apoptosis is significantly increased after CME. Caspase-12 may be involved in the apoptosis of cardiomyocyte after CME.