- Email: [email protected]
TCTAP A-051 Nicorandil Protects Cardiac Microvascular Endothelial Cells from Advanced Glycation End Products Induced Cytotoxicity by Promoting Autophagy
JOURNAL OF THE AMERICAN COLLEGE OF CARDIOLOGY, VOL. 69, NO. 16, SUPPL S, 2017
S27
TCTAP A-051 Nicorandil Protects Cardiac Microvascular Endothelial Cells from Advanced Glycation End Products Induced Cytotoxicity by Promoting Autophagy
vasoconstrictions to maximal acetylcholine infusion in the clopidogrel and prasugrel group compared with those in the ticagrelor group. There were no significant differences in all findings between clopidogrel and prasugrel groups.
Bing Hua,1 Qingbo Liu,1 Hehe Cui,1 Hui Chen,1 Hongwei Li1 1 Beijing Friendship Hospital, Capital Medical University, Beijing, China
CONCLUSION Compared to clopidogrel and prasugrel, ticagrelor reduced neointimal formation, endothelial dysfunction, and peristrut inflammation, which were indicators of neoatherosclerosis and late stent failure after drug-eluting stent implantation.
BACKGROUND Microvascular dysfunction is a primary comorbidity in diabetes mellitus (DM). Advanced glycation end products (AGEs) are well recognized pathogenic mediators in DM patients which could impair endothelium. Nicorandil, a KATP channel opener, is considered protective of the cardiac microvasculature. However, whether nicorandil could protect cardiac microvascular endothelial cells (CMECs) against AGEs-induced cytotoxicity is not clear. METHODS Human CMECs were exposed to different concentrations (50, 100, 200 mg/mL) of AGE-bovine serum albumin (AGE-BSA) for 24 hours to find work concentration. CMECs were treated with nicorandil at different concentration (10, 100, 1000 m mol) and AGE-BSA at 100 mmol for 24 hours. Wortmannin at 100 nmol was used to inhibit the PI3K/Akt signaling pathway and then suppress the upstream of autophagy. Chloroquine at 100 mmol was used to impede the downstream of autophagy. Viability and AGEs-induced cytotoxicity of CMECs were evaluated spectrophotometrically by a CCK-8 method. The proliferation and migration of CMECs were measured by scratch wound healing assays. Western blot was used to detect protein level. RESULTS AGE-BSA administration significantly reduced cellular viability, as identified with decreased optical density (OD) value at 450 nm evaluated by CCK8. Accordingly, AGE-BSA reduced migration measured by scratch wound healing assays in a dose-dependent manner (p<0.05). The dose of nicorandil at 100 mmol ameliorated the AGEs-induced cytotoxicity identified with increased OD value (Mean SEM, 1.503 0.196 in the Nicorandil 100 mmol group vs. 1.178 0.094 in the AGE-BSA 100 mg/mL group, p<0.05) evaluated by CCK8, and the scratch wound healing assays showed the same trend (p<0.05). However, nicorandil at 10 or 1000 mmol didn’t protect CMECs because of a lack of statistical significance. The inhibition of autophagy either by wortmannin or by chloroquine decreased the protective effects of nicorandil. Western blot revealed that phosphorylation of Akt was abrogated by wortmannin, which also decreased autophagy. The result of western blot demonstrated that autophagy was also suppressed by chloroquine, which was identified with increased type II of light chain 3 (LC3-II).
TCTAP A-053 Study of the Association Between Vasospasm and Serum Concentration of Aldehyde Dehydrogenase-2 in Patients with Variant Angina Kyu Tae Park1 1 Myongji Hospital, Korea (Republic of) BACKGROUND Vasospastic angina is caused by vasospasm of the coronary arteries. Aldehyde dehydrogenase 2 (ALDH2) is as the ethanol degradation pathway involved in nitroglycerin metabolism and reduces oxidative stress, thereby suppressing vasospasm. It is unclear whether a change in the blood expression levels of ALDH2 correlates with the regulation of vasospastic angina. So, we investigated alcohol ingestion and the concentration of ALDH2 about how it affect vasospastic angina. METHODS This was a prospective, single-center, observational study of 2,326 patients with angina who underwent coronary angiography between June 2011 and October 2014; of these, 195 patients underwent an intracoronary ergonovine provocation test because they presented symptoms indicative of vasospastic angina and proved for vasospastic angina.
CONCLUSION These results suggested that nicorandil could protect CMECs from AGE-induced cytotoxicity, and induction of autophagy via activating PI3K/Akt signaling pathway may be one of the mechanisms. TCTAP A-052 Effects of Ticagrelor on Neointimal Hyperplasia and Endothelial Function, Compared with Clopidogrel and Prasugrel, in a Porcine Coronary Stent Restenosis Model Hyun Kuk Kim,1 Myung-Ho Jeong,2 Kyung Seob Lim,2 Keun-Ho Park1 1 Chosun University Hospital, Korea (Republic of); 2Chonnam National University Hospital, Korea (Republic of) BACKGROUND Several investigations have been planned to evaluate the off-target effects of ticagrelor, but are not yet published. The aim of the present study was to evaluate the off-target effects of ticagrelor such as neointimal formation and endothelial function after drugeluting stent implantation in a porcine restenosis model. METHODS Eighteen pigs were prepared for this study. Three pigs (2 pigs with clopidogrel loading, 1 pig with ticagrelor loading) were excluded owing to significant vasoconstriction before percutaneous coronary intervention. A total of 15 pigs were randomly allocated based on the type of P2Y12 inhibitor. In each group, zotarolimuseluting stents were implanted in the proximal portion of the left anterior descending artery and left circumflex artery. One month after stenting, the animals underwent follow-up angiography, endothelial function assessment, optical coherence tomography (OCT) and histopathological analysis. RESULTS Percentages of mean neointimal area and area stenosis were significantly lower in the ticagrelor group than in the clopidogrel and prasugrel groups. There were strong positive correlations between OCT and histopathological parameters. Peri-strut inflammation scores were also significantly lower in the ticagrelor group. Regarding vasomotor responses to acetylcholine infusion, there were significant
RESULTS Angina symptoms induced by alcohol ingestion were noted in 13.3% of patients, half of whom had a positive response to ergonovine provocation. Vasospastic angina (i.e., positive response to ergonovine provocation) was noted in 39.0% of patients, who also had a higher difference between the pre-and post-test ALDH2 concentration (-10.00 4.53 vs -4.49 3.47 ng/mL in patients with a negative response; p¼0.03). Multivariate analysis revealed that vasospastic angina was significantly more prevalent in male subjects (odds ratio, 2.32; 95% confidence interval, 1.02–5.28). CONCLUSION The prevalence of angina symptoms induced by alcohol ingestion was 13.3%, and 50% of these patients had a positive response to ergonovine provocation. Furthermore, baseline ALDH2 levels were more elevated in patients with a positive response, and the difference in pre- and post-activation levels of ALDH2 was much larger in these patients. Finally, male sex was an independent risk factor for vasospastic angina in elderly patients (age65 years), whereas age was an independent risk factor only in middle-aged patients (age<65 years). We hope that our results will help clinicians to determine optimal therapeutic approaches for vasospastic angina.
S27
TCTAP A-051 Nicorandil Protects Cardiac Microvascular Endothelial Cells from Advanced Glycation End Products Induced Cytotoxicity by Promoting Autophagy
vasoconstrictions to maximal acetylcholine infusion in the clopidogrel and prasugrel group compared with those in the ticagrelor group. There were no significant differences in all findings between clopidogrel and prasugrel groups.
Bing Hua,1 Qingbo Liu,1 Hehe Cui,1 Hui Chen,1 Hongwei Li1 1 Beijing Friendship Hospital, Capital Medical University, Beijing, China
CONCLUSION Compared to clopidogrel and prasugrel, ticagrelor reduced neointimal formation, endothelial dysfunction, and peristrut inflammation, which were indicators of neoatherosclerosis and late stent failure after drug-eluting stent implantation.
BACKGROUND Microvascular dysfunction is a primary comorbidity in diabetes mellitus (DM). Advanced glycation end products (AGEs) are well recognized pathogenic mediators in DM patients which could impair endothelium. Nicorandil, a KATP channel opener, is considered protective of the cardiac microvasculature. However, whether nicorandil could protect cardiac microvascular endothelial cells (CMECs) against AGEs-induced cytotoxicity is not clear. METHODS Human CMECs were exposed to different concentrations (50, 100, 200 mg/mL) of AGE-bovine serum albumin (AGE-BSA) for 24 hours to find work concentration. CMECs were treated with nicorandil at different concentration (10, 100, 1000 m mol) and AGE-BSA at 100 mmol for 24 hours. Wortmannin at 100 nmol was used to inhibit the PI3K/Akt signaling pathway and then suppress the upstream of autophagy. Chloroquine at 100 mmol was used to impede the downstream of autophagy. Viability and AGEs-induced cytotoxicity of CMECs were evaluated spectrophotometrically by a CCK-8 method. The proliferation and migration of CMECs were measured by scratch wound healing assays. Western blot was used to detect protein level. RESULTS AGE-BSA administration significantly reduced cellular viability, as identified with decreased optical density (OD) value at 450 nm evaluated by CCK8. Accordingly, AGE-BSA reduced migration measured by scratch wound healing assays in a dose-dependent manner (p<0.05). The dose of nicorandil at 100 mmol ameliorated the AGEs-induced cytotoxicity identified with increased OD value (Mean SEM, 1.503 0.196 in the Nicorandil 100 mmol group vs. 1.178 0.094 in the AGE-BSA 100 mg/mL group, p<0.05) evaluated by CCK8, and the scratch wound healing assays showed the same trend (p<0.05). However, nicorandil at 10 or 1000 mmol didn’t protect CMECs because of a lack of statistical significance. The inhibition of autophagy either by wortmannin or by chloroquine decreased the protective effects of nicorandil. Western blot revealed that phosphorylation of Akt was abrogated by wortmannin, which also decreased autophagy. The result of western blot demonstrated that autophagy was also suppressed by chloroquine, which was identified with increased type II of light chain 3 (LC3-II).
TCTAP A-053 Study of the Association Between Vasospasm and Serum Concentration of Aldehyde Dehydrogenase-2 in Patients with Variant Angina Kyu Tae Park1 1 Myongji Hospital, Korea (Republic of) BACKGROUND Vasospastic angina is caused by vasospasm of the coronary arteries. Aldehyde dehydrogenase 2 (ALDH2) is as the ethanol degradation pathway involved in nitroglycerin metabolism and reduces oxidative stress, thereby suppressing vasospasm. It is unclear whether a change in the blood expression levels of ALDH2 correlates with the regulation of vasospastic angina. So, we investigated alcohol ingestion and the concentration of ALDH2 about how it affect vasospastic angina. METHODS This was a prospective, single-center, observational study of 2,326 patients with angina who underwent coronary angiography between June 2011 and October 2014; of these, 195 patients underwent an intracoronary ergonovine provocation test because they presented symptoms indicative of vasospastic angina and proved for vasospastic angina.
CONCLUSION These results suggested that nicorandil could protect CMECs from AGE-induced cytotoxicity, and induction of autophagy via activating PI3K/Akt signaling pathway may be one of the mechanisms. TCTAP A-052 Effects of Ticagrelor on Neointimal Hyperplasia and Endothelial Function, Compared with Clopidogrel and Prasugrel, in a Porcine Coronary Stent Restenosis Model Hyun Kuk Kim,1 Myung-Ho Jeong,2 Kyung Seob Lim,2 Keun-Ho Park1 1 Chosun University Hospital, Korea (Republic of); 2Chonnam National University Hospital, Korea (Republic of) BACKGROUND Several investigations have been planned to evaluate the off-target effects of ticagrelor, but are not yet published. The aim of the present study was to evaluate the off-target effects of ticagrelor such as neointimal formation and endothelial function after drugeluting stent implantation in a porcine restenosis model. METHODS Eighteen pigs were prepared for this study. Three pigs (2 pigs with clopidogrel loading, 1 pig with ticagrelor loading) were excluded owing to significant vasoconstriction before percutaneous coronary intervention. A total of 15 pigs were randomly allocated based on the type of P2Y12 inhibitor. In each group, zotarolimuseluting stents were implanted in the proximal portion of the left anterior descending artery and left circumflex artery. One month after stenting, the animals underwent follow-up angiography, endothelial function assessment, optical coherence tomography (OCT) and histopathological analysis. RESULTS Percentages of mean neointimal area and area stenosis were significantly lower in the ticagrelor group than in the clopidogrel and prasugrel groups. There were strong positive correlations between OCT and histopathological parameters. Peri-strut inflammation scores were also significantly lower in the ticagrelor group. Regarding vasomotor responses to acetylcholine infusion, there were significant
RESULTS Angina symptoms induced by alcohol ingestion were noted in 13.3% of patients, half of whom had a positive response to ergonovine provocation. Vasospastic angina (i.e., positive response to ergonovine provocation) was noted in 39.0% of patients, who also had a higher difference between the pre-and post-test ALDH2 concentration (-10.00 4.53 vs -4.49 3.47 ng/mL in patients with a negative response; p¼0.03). Multivariate analysis revealed that vasospastic angina was significantly more prevalent in male subjects (odds ratio, 2.32; 95% confidence interval, 1.02–5.28). CONCLUSION The prevalence of angina symptoms induced by alcohol ingestion was 13.3%, and 50% of these patients had a positive response to ergonovine provocation. Furthermore, baseline ALDH2 levels were more elevated in patients with a positive response, and the difference in pre- and post-activation levels of ALDH2 was much larger in these patients. Finally, male sex was an independent risk factor for vasospastic angina in elderly patients (age65 years), whereas age was an independent risk factor only in middle-aged patients (age<65 years). We hope that our results will help clinicians to determine optimal therapeutic approaches for vasospastic angina.