Utility and optimal dose of nicorandil for physiological assessment of the femoropopliteal artery.

BACKGROUND: Nicorandil is widely used as a vasodilator for the physiological assessment of coronary arteries because of its usefulness and safety; however, there are no data on its use in peripheral arteries. AIMS: To identify the utility of nicorandil and its appropriate dose for the physiological assessment on the femoropopliteal artery. METHODS: We retrospectively enrolled patients from three institutes in which physiological assessment was carried out with various doses of nicorandil before treatment. Twenty-four femoropopliteal artery stenotic lesions from 22 patients were included. The nicorandil doses used were 2, 4, and 6 mg. Twenty-two lesions were also assessed using 30 mg of papaverine. The pressure gradient (PG) and peripheral fractional flow reserve (pFFR) were calculated based on the mean and systolic pressure levels. We examined the correlation of each parameter with the peak systolic velocity ratio (PSVR) based on the duplex ultrasound images using Spearman's rank correlation coefficient. Systemic blood pressure was assessed for safety. RESULTS: The correlations were higher for mean pressure-based parameters than for systolic pressure-based parameters. As the nicorandil dose increased, the correlations among PG, pFFR, and PSVR also increased (mean pressure-based PG: 2 mg, r = 0.360; 4 mg, r = 0.498; 6 mg, r = 0.694, mean pressure-based pFFR: 2 mg, r = -0.479; 4 mg, r = -0.469; 6 mg, r = -0.641). The blood pressure after the administration of 6 mg of nicorandil was low, and the median systemic mean pressure was 65 mmHg. CONCLUSION: A 4 mg dose of nicorandil is effective and safe for the mean pressure-based physiological assessment of lesions in the femoropopliteal artery.

Nicorandil alleviates cardiac microvascular ferroptosis in diabetic cardiomyopathy: Role of the mitochondria-localized AMPK-Parkin-ACSL4 signaling pathway.

Mitochondria-associated ferroptosis exacerbates cardiac microvascular dysfunction in diabetic cardiomyopathy (DCM). Nicorandil, an ATP-sensitive K+ channel opener, protects against endothelial dysfunction, mitochondrial dysfunction, and DCM; however, its effects on ferroptosis and mitophagy remain unexplored. The present study aimed to assess the beneficial effects of nicorandil against endothelial ferroptosis in DCM and the underlying mechanisms. Cardiac microvascular perfusion was assessed using a lectin perfusion assay, while mitophagy was assessed via mt-Keima transfection and transmission electron microscopy. Ferroptosis was examined using mRNA sequencing, fluorescence staining, and western blotting. The mitochondrial localization of Parkin, ACSL4, and AMPK was determined via immunofluorescence staining. Following long-term diabetes, nicorandil treatment improved cardiac function and remodeling by alleviating cardiac microvascular injuries, as evidenced by the improved microvascular perfusion and structural integrity. mRNA-sequencing and biochemical analyses showed that ferroptosis occurred and Pink1/Parkin-dependent mitophagy was suppressed in cardiac microvascular endothelial cells after diabetes. Nicorandil treatment suppressed mitochondria-associated ferroptosis by promoting the Pink1/Parkin-dependent mitophagy. Moreover, nicorandil treatment increased the phosphorylation level of AMPKα1 and promoted its mitochondrial translocation, which further inhibited the mitochondrial translocation of ACSL4 via mitophagy and ultimately suppressed mitochondria-associated ferroptosis. Importantly, overexpression of mitochondria-localized AMPKα1 (mitoAα1) shared similar benefits with nicorandil on mitophagy, ferroptosis and cardiovascular protection against diabetic injury. In conclusion, the present study demonstrated the therapeutic effects of nicorandil against cardiac microvascular ferroptosis in DCM and revealed that the mitochondria-localized AMPK-Parkin-ACSL4 signaling pathway mediates mitochondria-associated ferroptosis and the development of cardiac microvascular dysfunction.

Efficacy and Safety of Nicorandil in the Treatment of Stable Angina Pectoris.

Background: Stable angina pectoris (SAP) is an ischemic heart disease caused by coronary artery stenosis, which usually occurs during physical activity or emotional excitement. For this type of angina pectoris, reducing the oxygen demand of the heart and increasing the coronary blood flow are the key goals of treatment. Objective: To analyze nicorandil's application effect and adverse reactions in patients with SAP. Methods: Sixty patients with stable angina pectoris admitted to our hospital from December 2020 to May 2022 were randomly selected and included in this study. They were divided into nicorandil group (n=30) and conventional group (n=30). The clinical efficacy, duration of chest pain, number of heart attacks per week, cardiac function indexes, improvement of exercise tolerance, occurrence of adverse reactions, and Seattle Angina Scale (SAQ) score were observed. Results: The effective rate of nicorandil group was 93.33%, which was much higher than that of conventional group (73.33%, P < .05). The results showed that the nicorandil group was significantly better than the conventional group in clinical efficacy, duration of chest pain, number of attacks per week, cardiac function index, improvement of exercise tolerance, occurrence of adverse reactions and SAQ score (P < .05). Conclusions: Nicorandil can improve the clinical symptoms of SAP patients, significantly reduce the duration and frequency of chest pain attacks, and enhance cardiac function indicators. It can be used as an effective drug choice to reduce the frequency and intensity of angina pectoris attacks and is worthy of wide clinical application.

Assessment of cardiac parameters after the administration of nicorandil before primary percutaneous coronary intervention.

Objective: To assess cardiac troponin I and creatine kinase-myocardial band levels, electrocardiogram changes and major adverse cardiac events after treatment with nicorandil before primary percutaneous coronary intervention. METHODS: The comparative, analytical study was conducted from October to November 2022 at the Pharmacology Department of Army Medical College, National University of Medical Sciences, Rawalpindi, Pakistan, in collaboration with the Rawalpindi Institute of Cardiology, Rawalpindi. The sample comprised ST-elevated myocardial infarction patients of either gender aged at least 30 years with an ejection fraction of at least 35% undergoing primary percutaneous coronary intervention. Participants were selected based on the above-mentioned inclusion and informed consent was taken before their enrolment in this research study. The sample was randomised into control group A receiving conventional acute coronary syndrome treatment, and intervention group B receiving nicorandil in addition to the conventional treatment. Cardiac troponin I and creatine kinase-myocardial band levels, electrocardiogram changes, and major adverse cardiac events noted and compared. Data was analysed using SPSS 26. RESULTS: Of the 140 patients, 70(50%) were in each of the 2 groups. In group B, 60(85.7%) patients achieved a completely settled ST segment on electrocardiogram compared to 25(35.7%) in group A (p=0.001). There was a significant inter-group difference with respect to cardiac troponin I value 6 hours after percutaneous coronary intervention and major adverse cardiac events (p<0.05), but creatine kinase-myocardial band level was no significantly different between the groups (p=0.761). Conclusion: Prophylactic use of nicorandil in ST-elevated myocardial infarction patients decreased the incidence of reperfusion injury.

Nicorandil protects podocytes via modulation of antioxidative capacity in acute puromycin aminonucleoside-induced nephrosis in rats.

Nephrotic syndrome, characterized by proteinuria and hypoalbuminemia, results from the dysregulation of glomerular podocytes and is a significant cause of end-stage kidney disease. Patients with idiopathic nephrotic syndrome are generally treated with immunosuppressive agents; however, these agents produce various adverse effects. Previously, we reported the renoprotective effects of a stimulator of the mitochondrial ATP-dependent K+ channel (MitKATP), nicorandil, in a remnant kidney model. Nonetheless, the cellular targets of these effects remain unknown. Here, we examined the effect of nicorandil on puromycin aminonucleoside-induced nephrosis (PAN) rats, a well-established model of podocyte injury and human nephrotic syndrome. PAN was induced using a single intraperitoneal injection. Nicorandil was administered orally at 30 mg/kg/day. We found that proteinuria and hypoalbuminemia in PAN rats were significantly ameliorated following nicorandil treatment. Immunostaining and ultrastructural analysis under electron microscopy demonstrated that podocyte injury in PAN rats showed a significant partial attenuation following nicorandil treatment. Nicorandil ameliorated the increase in the oxidative stress markers nitrotyrosine and 8-hydroxy-2-deoxyguanosine in glomeruli. Conversely, nicorandil prevented the decrease in levels of the antioxidant enzyme manganese superoxide dismutase in PAN rats. We found that mitochondrial Ca2+ uniporter levels in glomeruli were higher in PAN rats than in control rats, and this increase was significantly attenuated by nicorandil. We conclude that stimulation of MitKATP by nicorandil reduces proteinuria by attenuating podocyte injury in PAN nephrosis, which restores mitochondrial antioxidative capacity, possibly through mitochondrial Ca2+ uniporter modulation. These data indicate that MitKATP may represent a novel target for podocyte injury and nephrotic syndrome.NEW & NOTEWORTHY Our findings suggest that the mitochondrial Ca2+ uniporter may be an upstream regulator of manganese superoxide dismutase and indicate a biochemical basis for the interaction between the ATP-sensitive K+ channel and Ca2+ signaling. We believe that our study makes a significant contribution to the literature because our results indicate that the ATP-sensitive K+ channel may be a potential therapeutic target for podocyte injury and nephrotic syndrome.

Nicorandil Exerts Anticonvulsant Effects in Pentylenetetrazol-Induced Seizures and Maximal-Electroshock-Induced Seizures by Downregulating Excitability in Hippocampal Pyramidal Neurons.

N-(2-hydroxyethyl) nicotinamide nitrate (nicorandil), a nitrate that activates adenosine triphosphate (ATP)-sensitive potassium (KATP) channels, is generally used in the treatment of angina and offers long-term cardioprotective effects. It has been reported that several KATP channel openers can effectively alleviate the symptoms of seizure. The purpose of this study was to investigate the improvement in seizures induced by nicorandil. In this study, seizure tests were used to evaluate the effect of different doses of nicorandil by analysing seizure incidence, including minimal clonic seizure and generalised tonic-clonic seizure. We used a maximal electroshock seizure (MES) model, a metrazol maximal seizure (MMS) model and a chronic pentylenetetrazol (PTZ)-induced seizure model to evaluate the effect of nicorandil in improving seizures. Each mouse in the MES model was given an electric shock, while those in the nicorandil group received 0.5, 1, 2, 3 and 6 mg/kg of nicorandil by intraperitoneal injection, respectively. In the MMS model, the mice in the PTZ group and the nicorandil group were injected subcutaneously with PTZ (90 mg/kg), and the mice in the nicorandil group were injected intraperitoneally with 1, 3 and 5 mg/kg nicorandil, respectively. In the chronic PTZ-induced seizure model, the mice in the PTZ group and the nicorandil group were injected intraperitoneally with PTZ (40 mg/kg), and the mice in the nicorandil group were each given 1 and 3 mg/kg of PTZ at a volume of 200 nL. Brain slices containing the hippocampus were prepared, and cell-attached recording was used to record the spontaneous firing of pyramidal neurons in the hippocampal CA1 region. Nicorandil (i.p.) significantly increased both the maximum electroconvulsive protection rate in the MES model and the seizure latency in the MMS model. Nicorandil infused directly onto the hippocampal CA1 region via an implanted cannula relieved symptoms in chronic PTZ-induced seizures. The excitability of pyramidal neurons in the hippocampal CA1 region of the mice was significantly increased after both the acute and chronic administration of PTZ. To a certain extent, nicorandil reversed the increase in both firing frequency and proportion of burst spikes caused by PTZ (P < 0.05). Our results suggest that nicorandil functions by downregulating the excitability of pyramidal neurons in the hippocampal CA1 region of mice and is a potential candidate for the treatment of seizures.

Cardioprotective and Antianginal Efficacy of Nicorandil: A Comprehensive Review.

ABSTRACT: Angina pectoris remains a significant burden despite advances in medical therapy and coronary revascularization. Many patients (up to 30%) with angina have normal coronary arteries, with coronary microvascular disease and/or coronary artery vasospasm being major drivers of the myocardial demand-supply mismatch. Even among patients revascularized for symptomatic epicardial coronary stenosis, recurrent angina remains highly prevalent. Medical therapy for angina currently centers around 2 disparate goals, viz secondary prevention of hard clinical outcomes and symptom control. Vasodilators, such as nitrates, have been first-line antianginal agents for decades, along with beta-blockers and calcium channel blockers. However, efficacy in symptoms control is heterogenous, depending on underlying mechanism(s) of angina in an individual patient, often necessitating multiple agents. Nicorandil (NCO) is an antianginal agent first discovered in the late 1970s with a uniquely dual mechanism of action. Like a typical nitrate, it mediates medium-large vessel vasodilation through nitric oxide. In addition, NCO has adenosine triphosphate (ATP)-dependent potassium channel agonist activity (K ATP ), mediating microvascular dilatation. Hence, it has proven effective in both coronary artery vasospasm and coronary microvascular disease, typically challenging patient populations. Moreover, emerging evidence suggests that cardiomyocyte protection against ischemia through ischemic preconditioning may be mediated through K ATP agonism. Finally, there is now fairly firm evidence in favor of NCO in terms of hard event reduction among patients with stable coronary artery disease, following myocardial infarction, and perhaps even among patients with congestive heart failure. This review aims to summarize the mechanism of action of NCO, its efficacy as an antianginal, and current evidence behind its impact on hard outcomes. Finally, we review other cardiac and emerging noncardiac indications for NCO use.

Nicorandil Ameliorates Doxorubicin-Induced Cardiotoxicity in Rats, as Evaluated by 7 T Cardiovascular Magnetic Resonance Imaging.

PURPOSE: Doxorubicin-induced cardiotoxicity (DIC) is a common side effect of doxorubicin chemotherapy, and a major mechanism of DIC is inflammation. However, no effective method exists to prevent DIC. In the present study, we investigated the cardioprotective effects of nicorandil against DIC using multiparametric cardiac magnetic resonance (CMR) imaging and elucidated the anti-inflammatory properties of nicorandil in rat models. METHODS: Male Sprague-Dawley rats received four weekly intraperitoneal doxorubicin doses (4 mg/kg/injection) to establish the DIC model. After treatment with or without nicorandil (3 mg/kg/day) or diazoxide (10 mg/kg/day) orally, all the groups underwent weekly CMR examinations, including cardiac function and strain assessment and T2 mapping, for 6 weeks. Additionally, blood samples and hearts were collected to examine inflammation and histopathology. RESULTS: According to our results, the earliest DIC CMR parameter in the doxorubicin group was T2 mapping time prolongation compared with the DIC rats treated with nicorandil (doxorubicin+nicorandil group) at week 2. Subsequently, the left ventricular ejection fraction (LVEF) and global peak systolic myocardial strain in the doxorubicin group were significantly reduced, and nicorandil effectively inhibited these effects at week 6. Our results were confirmed by histopathological evaluations. Furthermore, nicorandil treatment had a protective effect against the doxorubicin-induced inflammatory response. Interestingly, similar protective results were obtained using the KATP channel opener diazoxide. CONCLUSION: Collectively, our findings indicate that nicorandil application ameliorates DIC in rats with significantly higher cardiac function and myocardial strain and less fibrosis, apoptosis and inflammatory cytokine production. Nicorandil prevents T2 abnormalities in the early stages of DIC, showing a high clinical value for early nicorandil treatment in chemotherapy patients.

Nicorandil Suppresses Ischemia-Induced Norepinephrine Release and Ventricular Arrhythmias in Hypertrophic Hearts.

PURPOSE: Ventricular arrhythmias (VAs) are a common cause of sudden death in acute myocardial infarction (MI), for which hypertension is a major risk factor. Nicorandil opens ATP-sensitive potassium (KATP) channels, which are expressed by nerve terminals and cardiomyocytes and regulate the release of norepinephrine (NE). However, the effects of nicorandil on ischemic NE release in cardiac tissue remain unclear. Therefore, we herein investigated whether nicorandil suppressed interstitial NE concentrations and VAs during acute MI in pressure overload-induced hypertrophic hearts. METHODS: Rats were divided into two groups: an abdominal aortic constriction (AAC) group and sham-operated (Sham) group. Four weeks after constriction, cardiac geometry and functions were examined using echocardiography and hemodynamic analyses. Myocardial ischemia was induced by coronary artery occlusion for 100 min with or without the administration of nicorandil. VAs were assessed by electrocardiography, and NE concentrations in the ischemic region were measured using a micro-dialysis method. RESULTS: AAC induced left ventricular hypertrophy with diastolic dysfunction. VAs markedly increased in the early phase (0-20 min) of ischemia in both groups and were more frequent in the AAC group. Cardiac interstitial NE concentrations were higher in the AAC group before ischemia and significantly increased during ischemia in both groups. Nicorandil significantly suppressed ischemia-induced VAs and NE increases in the AAC group. CONCLUSION: Ischemia-induced VAs were more frequent in hypertrophic hearts and associated with high interstitial concentrations of NE. The attenuation of ischemia-induced increases in NE through neuronal KATP opening by nicorandil may suppress ischemia-induced VAs in hypertrophic hearts.

Intravenous nicorandil for patients with acute decompensated heart failure: a meta-analysis of randomized controlled trials.

OBJECTIVES: Pilot studies have suggested the potential benefits of intravenous nicorandil for patients with acute decompensated heart failure (ADHF). However, clinical evidence remains limited. The aim of the study was to summarize the efficacy and safety of intravenous nicorandil for the treatment of ADHF. DESIGN: A systematic review and meta-analysis was performed. The search for relevant randomised controlled trials (RCTs) was conducted in PubMed, Embase, Cochrane's Library, Wanfang, and CNKI databases. A random-effects model was employed to combine the results. RESULTS: Eight RCTs contributed to the meta-analysis. Pooled results showed that acute treatment with intravenous nicorandil could significantly improve the symptom of dyspnea at 24 h after treatment, as evidenced by the five-point Likert scale for dyspnea after treatment (mean difference [MD]: -0.26, 95% confidence interval [CI]: -0.40 to -0.13, p < 0.001). Furthermore, nicorandil significantly reduced serum B natriuretic peptide (MD: -30.03 ng/dl, 95% CI: -47.00 to -13.06, p < 0.001), and N-terminal proBNP (MD: -138.69, 95% CI: -248.06 to -29.31, p = 0.01). In addition, nicorandil significantly improved ultrasonic parameters including left ventricular ejection fraction and E/e' at discharge. Moreover, during the follow-up duration of up to 90 days, intravenous nicorandil significantly reduced the incidence of major adverse cardiovascular events (risk ratio [RR]: 0.55, 95% CI: 0.32 to 0.93, p = 0.03). The incidence of treatment-related adverse events was not significantly different between nicorandil and controls (RR: 1.22, 95% CI: 0.69 to 2.15, p = 0.49). CONCLUSIONS: Results of this study suggest that intravenous nicorandil may be an effective and safe treatment for patients with ADHF.

Nicorandil mitigates amiodarone-induced pulmonary toxicity and fibrosis in association with the inhibition of lung TGF-ß1/PI3K/Akt1-p/mTOR axis in rats.

The long-term side effect of the antiarrhythmic drug, amiodarone (AMIO), such as lung toxicity, remains a critical clinical issue. The previous knowledge denotes diverse antioxidant, anti-inflammatory, and antifibrotic properties of the anti-anginal drug, nicorandil (NI). Therefore, we aimed to investigate the possible protective effect of NI on pulmonary tissue remodelling following AMIO-induced lung toxicity. The included rats were assigned into four equal groups (n = 8): (1) control, (2) control group that received NI 10 mg kg-1  day-1 , (3) model group that received AMIO in a dose of 60 mg kg-1  day-1 , and (4) treated group (AMIO-NI) that were treated with AMIO plus NI as shown above. Drug administration continued for 10 weeks. AMIO resulted in deteriorated (p < 0.001) pulmonary functions accompanied by respiratory acidosis. AMIO showed an obvious histological injury score with intense collagen deposition, disturbed nitric oxide synthase enzymes (NOS/iNOS), and increased alpha smooth muscle actin expression. Furthermore, AMIO upregulated the transforming growth factor (TGF-ß1)/phosphoinositide-3 kinase (PI3K)-Akt1-p/mammalian target of rapamycin (mTOR) axis, which determined the possible mechanism of AMIO on pulmonary remodelling. NI treatment significantly (p < 0.001) prevented the AMIO-induced lung toxicity, as well as inhibited the TGF-ß1/PI3K/Akt1-p/mTOR axis in the lung tissue of rats. The results were confirmed by an in-vitro study. CONCLUSION: The current results revealed that NI was effective in preserving the lung structure and functions. Amelioration of the oxidative stress and modulation of TGF-ß1/PI3K/Akt1-p/mTOR have been achieved. This study suggests NI administration as a preventive therapy from the serious pulmonary fibrosis side effect of AMIO.

Exploring the role of ATP-sensitive potassium channel, eNOS, and P-glycoprotein in mediating the hepatoprotective activity of nicorandil in methotrexate-induced liver injury in rats.

BACKGROUND: Methotrexate (MTX) is a commonly used chemotherapeutic agent; however, its clinical use is challenged by various types of injuries, including hepatotoxic side effects. Therefore, finding new protective drugs against MTX-induced toxicities is a critical need. Moreover, the different mechanisms mediating such effects are still not clear. The current study aimed to evaluate the possible ameliorative action of nicorandil (NIC) in MTX-induced hepatotoxicity and examine the roles of the ATP-sensitive potassium channel (KATP), endothelial nitric oxide synthase (eNOS), and P-glycoprotein (P-gp). MATERIALS AND METHODS: Thirty-six male Wistar albino rats were used. NIC (3 mg/kg/day) was given orally for 2 weeks, and hepatotoxicity was induced by a single intraperitoneal injection of MTX (20 mg/kg) on the 11th day of the experiment. We confirmed the role of KATP by co-administering glimepiride (GP) (10 mg/kg/day) 30 min before NIC. The measured serum biomarkers were [alanine transaminase (ALT) and aspartate transaminase (AST)], total antioxidant capacity (TAC), malondialdehyde (MDA), nitric oxide (NOx), tumor necrosis factor-alpha (TNFα), superoxide dismutase (SOD), and P-gp. Histopathology, eNOS, and caspase-3 immunoexpression were evaluated. RESULTS: The MTX group displayed hepatotoxicity in the form of elevations of ALT, AST, MDA, NOx, and caspase-3 immunoexpression. Furthermore, the histopathological examination showed marked liver injury. TAC, SOD, P-gp, and eNOS immunoexpression showed significant inhibition. In the protective group, all parameters improved (P value < 0.05). CONCLUSION: NIC has an ameliorative action against MTX-induced hepatotoxicity, most probably via its antioxidant, anti-inflammatory, and anti-apoptotic functions together with the modulation of the KATP channel, eNOS, and P-glycoprotein.

Effectiveness of intraoperative nicorandil in patients with a history of ischemic heart disease undergoing high-risk noncardiac surgery: a retrospective cohort study.

PURPOSE: Nicorandil is occasionally administered to prevent myocardial ischemia during the perioperative period in patients with ischemic heart disease (IHD); however, its effectiveness has not been clarified. In this study, we examined the effectiveness of intraoperative nicorandil administration in noncardiac surgery. METHODS: We identified patients with a history of IHD who had undergone high-risk noncardiac surgery between April 2015 and March 2020 from a nationwide in-patient database in Japan. The patients were divided into those who received nicorandil (nicorandil group) and those who did not (control group). The primary outcome was the 30-day in-hospital mortality. The secondary outcome was major adverse cardiovascular events (MACE), defined as the composite outcome of the 30-day in-hospital mortality, acute myocardial infarction, percutaneous coronary intervention, and coronary artery bypass grafting. One-to-one propensity score matching was performed. The outcomes were analyzed using a Cox proportional hazards model. RESULTS: Of 8037 patients, 2886 received nicorandil during surgery. After propensity score matching, 2554 pairs were analyzed. There was no significant difference in the 30-day in-hospital mortality (26 [1.02%] vs. 36 [1.41%]; hazard ratio [HR] 1.36; 95% confidence interval [CI] 0.82-2.26; P = 0.229) or incidence of MACE (42 [1.64%] vs. 55 [2.15%]; HR 1.24; 95% CI 0.86-1.93; P = 0.216) between the control and nicorandil groups. CONCLUSION: The findings of this study suggest that intraoperative nicorandil administration is not associated with the 30-day in-hospital mortality in high-risk noncardiac surgery.

Intravenous nicorandil during primary percutaneous coronary intervention in patients with ST-Elevation myocardial infarction: Rationale and design of the Clinical Efficacy and Safety of Intravenous Nicorandil (CLEAN) trial.

BACKGROUND: The efficacy and safety of intravenous infusion of nicorandil during primary percutaneous coronary intervention (PCI) in patients with ST-elevation myocardial infarction (STEMI) remain uncertain. OBJECTIVES: The primary objective of the CLinical Efficacy and sAfety of intravenous Nicorandil (CLEAN) trial is to evaluate the long-term efficacy and safety of intravenous administration of nicorandil as adjuncts to reperfusion therapy in patients with STEMI undergoing primary PCI. DESIGN: The CLEAN trial is a multicenter, randomized, double-blind, placebo-controlled trial that will enroll 1,500 patients from 40 centers across china. patients were randomly (1:1) assigned to receive intravenous nicorandil (6 mg as a bolus before reperfusion, followed by 48 hours of continuous infusion at a dose of 6 mg/h after coronary intervention) or the same dose of placebo according to randomization. The primary efficacy outcome was a composite of death from cardiovascular causes, nonfatal myocardial infarction, target vessel revascularization, and unplanned hospitalization for heart failure within 12 months. The secondary efficacy outcomes included the individual components of the combined efficacy endpoint, incidence of slow coronary flow after PCI, and incidence of complete ST-segment resolution at 2 hours after PCI. the safety outcomes included the incidence of hypotension after drug infusion and other adverse events during medication. SUMMARY: CLEAN will determine whether the addition of intravenous nicorandil as adjuncts to reperfusion therapy reduces the major adverse cardiovascular events in STEMI patients undergoing primary PCI. TRIAL REGISTRATION: ClinicalTrials.gov, NCT04665648.

Protective effect of nicorandil against myocardial ischemia/reperfusion injury mediated via IL33/ST2 signaling pathway.

Myocardial ischemia-reperfusion injury (MI/RI), a complication of myocardial injury, is associated with high rates of mortality and disability. We aimed to explore the effect of nicorandil™ against MI/RI and investigated the underlying molecular mechanisms. In this in vitro study, hypoxia/reoxygenation (H/R) processing of H9c2 cells significantly suppressed the expressions of IL33 and ST2, reduced cell viability, increased production of reactive oxygen species, downregulated protein expression of Bcl-2, upregulated protein expressions of Bax, cleaved caspase3, and cleaved PARP, increased intracellular calcium overload, and induced cell apoptosis. Nicorandil processing reduced H/R-induced H9c2 cell damage. Nicorandil processing ameliorated the H/R-induced inhibition of the IL33 and ST2 expression in H9c2 cells. 5-Hydroxydecanoate blocked the effects of nicorandil on H9c2 cell viability, ROS production, and apoptosis and inhibited both IL33 and ST2. Similarly, the protective effect of nicorandil was restrained after inhibition of the IL33/ST2 pathway. Our findings suggest that the protective effect of nicorandil against H/R-induced H9c2 cell apoptosis was mediated through IL33/ST2 signaling pathway.

CoO Nanoparticles Combined with MRI: Analysis of No-Reflow in Patients with Acute ST-Segment Elevation Myocardial Infarction after PCI and the Effect of Coronary Nicorandil.

Magnetic resonance imaging (MRI) has become one of the most important medical imaging techniques in the clinic due to its high degree of soft tissue resolution and no radiation damage, and it plays an important role in the early diagnosis and treatment of tumors. This article mainly studies the analysis of no-reflow in patients with acute ST-segment elevation myocardial infarction after PCI and the effect of coronary nicorandil on CoO nanoparticles combined with MRI. In this paper, the synthesized water-soluble nanoparticles are dispersed in a 2% xanthan gum or agarose solution. In an MRI analyzer, the T1 value is tested with the inversion recovery sequence, and the T2 value is tested with the hard pulse CPMG sequence. The gyroscope imaging sequence performs T1-weighted and T2-weighted imaging tests. Calculated densitometry (QCA) was used to measure the stenosis of the coronary lesions, the length of the lesions and the diameter of the lumen before stent implantation. In order to facilitate the collection of urine samples, this article adopts the method of inserting a catheter to drain the patient for sampling. From the baseline state at the time of enrollment to 150 minutes after PCI, polyethylene containing 0.1% butylated hydroxyanisole is used. Urine samples were taken from the test tube every 30 minutes, a total of 6 times were collected, and the collected urine samples were stored in a low-temperature refrigerator at -80℃ for the final inspection. This paper uses calculation software to calculate the risk of death and death/myocardial infarction in the hospital and at 6 months after discharge. The data showed that the postoperatively detected CKMB and cTnI were higher than those before the operation, but the peak value of the nicorandil group was lower than that of the control group, but there was still no statistical difference (P>0.05). The results show that nicorandil can significantly improve the no-reflow phenomenon in AMI patients during PCI.

Protective effect of ischaemic postconditioning combined with nicorandil on myocardial ischaemia‒reperfusion injury in diabetic rats.

BACKGROUND: The diabetic heart exhibits a high sensitivity to ischaemia/reperfusion (I/R) injury. Diabetes mellitus (DM) can affect the efficacy of cardioprotective interventions and reduce the therapeutic potential of existing treatment options. This study aimed to investigate the feasibility of shifting from monotherapy to combination therapy in diabetic myocardial I/R injury. METHODS: 6-8 week rats were randomized into 10 groups: sham, I/R, ischaemia postconditioning (I-Post), nicorandil (Nic), combination therapy (I-Post + Nic), DM sham, DM I/R, DM I-Post, DM Nic and DM I-Post + Nic. The extent of myocardial injury was clarified by measuring CK-MB and NO levels in plasma, ROS content in myocardial tissues, and TTC/Evans Blue staining to assess the area of myocardial infarction. Pathological staining of cardiac tissue sections were performed to clarify the structural changes in myocardial histopathology. Finally, Western blotting was performed to detect the phosphorylation levels of some key proteins in the PI3K/Akt signalling pathway in myocardial tissues. RESULTS: We confirms that myocardial injury in diabetic I/R rats remained at a high level after treatment with I-Post or nicorandil alone. I-Post combined with nicorandil showed better therapeutic effects in diabetic I/R rats, and the combined treatment further reduced the area of myocardial injury in diabetic I/R rats compared with I-Post or nicorandil treatment alone (P < 0.001), as well as the levels of the myocardial injury markers CK-MB and ROS (P < 0.001); it also significantly increased plasma NO levels. Pathological staining also showed that diabetic rats benefited significantly from the combination therapy. Further mechanistic studies confirmed this finding. The protein phosphorylation levels of PI3K/Akt signalling pathway in the heart tissue of diabetic I/R rats were significantly higher after the combination treatment than after one treatment alone (all P < 0.05). CONCLUSION: I-Post combined with nicorandil treatment maintains effective cardioprotection against diabetic myocardial I/R injury by activating the PI3K/Akt signalling pathway.

Effectiveness and Safety of Intravenous Nicorandil Application in Patients With Acute Heart Failure With Low Baseline Blood Pressure.

AIM: To evaluate the effectiveness and safety of intravenous nicorandil application in patients with acute heart failure (AHF) with low baseline blood pressure (systolic blood pressure <110 mmHg). METHOD: This prospective, controlled, single-centre study randomised 147 patients with AHF with low baseline blood pressure (including both emergent admission and newly developed low blood pressure while in hospital) to one of the following two groups: (1) control group (conventional diuretics, positive inotropic agents, and related therapy according to the guidelines); and (2) intervention group (intravenous [IV] nicorandil application plus routine care). Dyspnoea severity, the ratio of E to e' (E/e'), the incidence of side effects and adverse events, N-terminal pro-brain natriuretic peptide (NT-proBNP) level, left ventricular ejection fraction (LVEF; left ventricular systolic function) before discharge, average length of hospitalisation, LVEF and soluble suppression of tumorigenicity-2 (sST2) at 3 months after discharge, incidence of major adverse cardiac and cerebrovascular events (MACCE) and readmission rate within 3 months were recorded and compared between the two groups. RESULTS: Compared to the control group, nicorandil relieved dyspnoea effectively and improved E/e' significantly; the level of NT-proBNP was lower, LVEF was higher before discharge, and average length of hospital stay was shorter in the intervention group. After 3 months, the LVEF was higher, sST2 was lower, and the readmission rate was lower in the intervention group; there was no statistically significant difference in MACCE. CONCLUSIONS: Patients with AHF with low baseline blood pressure could benefit from IV nicorandil application in the urgent phase, but the long-term profits remained to be confirmed.

Nicorandil, an ATP-sensitive potassium channel activation, attenuates myocardial injury in rats with ischemic cardiomyopathy.

Ischemic cardiomyopathy is a common but underestimated cause of heart failure. This study investigated the myocardial-protective effects of nicorandil on rats with ischemic cardiomyopathy. In the present study, ischemic cardiomyopathy rats model were used to evaluate the effects of nicorandil. Cardiac ultrasonography was employed to examine the changes of heart structure and heart function. Electron microscopy was employed to observe the changes of pathological ultrastructure of the myocardium. Western blot and enzyme-linked immunosorbent assays were employed to detect protein levels and Mitochondrial Ca2+ concentration. The heart color ultrasound and myocardial pathology of the rats in the nicorandil group were improved significantly, the mitochondrial Ca2+ concentration was decreased, the expressions of MFN-1, OPA-1, and Bcl were increased, and the expressions of the mitochondrial mitotic proteins DRP-1, VDAC1, CytC, and Bax were decreased in ICM rats' heart treatment with nicorandil, compared with ICM rats. Nicorandil can reduce myocardial pathological damage in ICM rats, which may be caused by promoting the opening of mitochondrial ATP-sensitive potassium channel and inducing the changes of mitochondrial dynamics to induce the reduction of myocardial cell apoptosis.

Changes of Pulmonary Microhemodynamics in Experimental Pulmonary Thromboembolism after Pretreatment with K-Channel Activators.

Changes in pulmonary microhemodynamics in response to pulmonary embolism under conditions of activation of KATP channels with nicorandil, Kv channels with dapagliflozin, and BKCa channels with Evans blue were studied on isolated rabbit lungs. Under conditions of activation of KATP and BKCa channels, the constrictor reactions of the pulmonary arterial vessels during embolization of the pulmonary artery were less pronounced than in the control. Activation of BKCa channels reduced constrictor reactions of the pulmonary venous vessels, while activation of KATP and Kv channels eliminates them. The shifts of the capillary filtration coefficient are determined to a greater extent by the pre-/postcapillary resistance ratio, than by changes of the endothelial permeability. Pretreatment with dapagliflozin led to a decrease in the capillary filtration coefficient. It was established, that nimesulide exhibits properties of a BKCa-channel activator.