Protective Mechanism of Trimetazidine in Myocardial Cells in Myocardial Infarction Rats through ERK Signaling Pathway

Retracted: Protective Mechanism of Trimetazidine in Myocardial Cells in Myocardial Infarction Rats through ERK Signaling Pathway

[This retracts the article DOI: 10.1155/2021/9924549.].

Activation of AHR by ITE improves cardiac remodelling and function in rats after myocardial infarction

AIMS

Left ventricular remodelling subsequent to myocardial infarction (MI) constitutes a pivotal underlying cause of heart failure. Intervention with the nontoxic endogenous aryl hydrocarbon receptor (AHR) agonist 2-(1'H-indole-3'-carbonyl)-thiazole-4-carboxylic acid methyl ester (ITE) in the acute phase of MI has been shown to ameliorate cardiac function, but its role in the chronic phase remains obscured. This study explores the beneficial role of ITE in delaying the progression of heart failure in the chronic phase of MI.

METHODS AND RESULTS

MI rats established by ligating the left anterior descending coronary artery were treated with the indicated concentration of the AHR agonist ITE or vehicle alone. Echocardiography was performed to determine cardiac structure and function; myocardial morphology and fibrosis were observed by haematoxylin and eosin and Masson's trichrome staining; serum biochemical indices, BNP, and inflammatory cytokine levels were detected by enzyme-linked immunosorbent assay; F4/80+ iNOS+ M1 macrophages and F4/80+ CD206+ M2 macrophages were detected by immunofluorescence; the terminal deoxynucleotidyl transferase-mediated dUTP nick end labelling assay was used to detect the apoptosis of cardiomyocytes; ultrastructural changes in myocardial tissue were observed by transmission electron microscopy; and Cyp1a1, Akt, P-Akt, p70S6K, P-p70S6K, Bcl-2, Bax, caspase-3, and cleaved caspase-3 protein levels were determined via Western blotting. We found that therapy with the AHR agonist ITE rescued cardiac remodelling and dysfunction in rats with MI and attenuated myocardial fibrosis, inflammation, and mitochondrial damage. Further studies confirmed that ITE dose-dependently improved myocardial cell apoptosis after MI, as demonstrated by reduced levels of the apoptosis-related proteins cleaved caspase-3 and Bax but increased expression levels of Bcl-2. These effects were attributed to ITE-induced activation of AHR receptors, leading to the down-regulation of Akt and p70S6K phosphorylation.

CONCLUSIONS

The AHR agonist ITE alleviates cardiomyocyte apoptosis through the Akt/p70S6K signalling pathway, thereby rescuing left ventricular adverse remodelling and cardiac dysfunction after MI.

Metabolic regulation to treat bipolar depression: mechanisms and targeting by trimetazidine

Bipolar disorder's core feature is the pathological disturbances in mood, often accompanied by disrupted thinking and behavior. Its complex and heterogeneous etiology implies that a range of inherited and environmental factors are involved. This heterogeneity and poorly understood neurobiology pose significant challenges to existing drug development paradigms, resulting in scarce treatment options, especially for bipolar depression. Therefore, novel approaches are needed to discover new treatment options. In this review, we first highlight the main molecular mechanisms known to be associated with bipolar depression-mitochondrial dysfunction, inflammation and oxidative stress. We then examine the available literature for the effects of trimetazidine in said alterations. Trimetazidine was identified without a priori hypothesis using a gene-expression signature for the effects of a combination of drugs used to treat bipolar disorder and screening a library of off-patent drugs in cultured human neuronal-like cells. Trimetazidine is used to treat angina pectoris for its cytoprotective and metabolic effects (improved glucose utilization for energy production). The preclinical and clinical literature strongly support trimetazidine's potential to treat bipolar depression, having anti-inflammatory and antioxidant properties while normalizing mitochondrial function only when it is compromised. Further, trimetazidine's demonstrated safety and tolerability provide a strong rationale for clinical trials to test its efficacy to treat bipolar depression that could fast-track its repurposing to address such an unmet need as bipolar depression.

The imPAct of Trimetazidine on MicrOcirculation after Stenting for stable coronary artery disease (PATMOS study)

Background

Myocardial ischemia is caused by epicardial coronary artery stenosis or atherosclerotic disease affecting microcirculation. Trimetazidine (TMZ), promotes glucose oxidation which optimizes cellular energy processes in ischemic conditions. Small studies demonstrated protective effects of TMZ in terms of reducing myocardial injury after percutaneous coronary intervention (PCI), its effect on microcirculation using contemporary investigative methods has not been studied. The aim of the study was to examine effects of trimetazidine, given before elective PCI, on microcirculation using invasively measured index of microcirculatory resistance (IMR).

Methods

This was prospective, single blinded, randomized study performed in a single university hospital. It included consecutive patients with an indication for PCI of a single, de novo, native coronary artery lesion. Patients were randomly assigned to receive either TMZ plus standard therapy (TMZ group) or just standard therapy. Coronary physiology indices fractional flow reserve (FFR), coronary flow reserve (CFR) and index of microcirculatory resistance (IMR) were measured before and after PCI using coronary pressure wire.

Results

We randomized 71 patients with similar clinical characteristics and risk profile, previous medications and coronary angiograms. Patientshad similar values of Pd/Pa, FFR and CFR prior to PCI procedure. After PCI, FFR values were higher in TMZ group, while IMR values were lower in this group respectively (FFR TMZ + 0.89 ± 0.05 vs. TMZ - 0.85 ± 0.06, p = 0.007; CFR TMZ + 2.1 ± 0.8 vs. TMZ- 2.3 ± 1.3, p = 0.469; IMR TMZ + 18 ± 9 vs. TMZ- 24 ± 12, p = 0.028). In two-way repeated measures ANOVA PCI was associated with change in FFR values (TMZ p = 0.050; PCI p < 0.001; p for interaction 0.577) and TMZ with change in IMR values (TMZ p = 0.034, PCI p = 0.129, p for interaction 0.344).

Conclusion

Adding trimetazidine on top of medical treatment prior to elective PCI reduces microvascular dysfunction by lowering postprocedural IMR values when compared to standard therapy alone.

Effect and mechanism of Tangzhiqing in improving cardiac function in mice with hyperlipidaemia complicated with myocardial ischaemia

Purpose

Tangzhiqing formula (TZQ) is a traditional Chinese medicine prescribed to treat lipid metabolism disorders, atherosclerosis, diabetes and diabetic cardiomyopathy. However, some challenges and hurdles remain. TZQ showed promising results in treating diabetes and hyperlipidaemia. However, its effect on and mechanism of action in hyperlipidaemia complicated with myocardial ischaemia (HL-MI) remain unknown.

Methods

In this study, a network pharmacology-based strategy integrating target prediction was adopted to predict the targets of TZQ relevant to the treatment of HL-MI and to further explore the involved pharmacological mechanisms.

Results

A total of 104 potential therapeutic targets were obtained, including MMP9, Bcl-2, and Bax, which may be related to the apoptosis and PI3K/AKT signalling pathways. Then, we confirmed these potential targets and pathways with animal experimentation. TZQ reduced lipid levels, increased the expression levels of Bcl-2, decreased Bax, caspase-3 and caspase-9 expression levels, and activated the PI3K/AKT signalling pathway.

Conclusion

In conclusion, this study provides new insights into the protective mechanisms of TZQ against HL-MI through network pharmacology and pharmacological approaches.

Blocking the A2B adenosine receptor alleviates myocardial damage by inhibiting spleen-derived MDSC mobilisation after acute myocardial infarction

BACKGROUND

Myeloid-derived suppressor cell (MDSC) mobilisation is an important immune event in acute myocardial infarction (AMI). The A_2B adenosine receptor (A_2BAR) plays key role in regulating MDSC function, but its specific involvement in MDSC mobilisation in AMI remains unclear.

METHODS

In AMI patients, the circulating MDSC ratio and A_2BAR mRNA expression were measured. A mouse AMI model was established by left anterior descending coronary artery (LADCA) ligation. MDSCs were analysed by FACS and immunofluorescence staining (of heart tissue). A_2BAR mRNA expression was assessed by qRT-PCR. Myocardial injury was detected by HE staining. Myocardial cell apoptosis was analysed by immunohistochemistry. Cardiac systolic function was evaluated by transthoracic echocardiography.

RESULTS

In AMI patients, the circulating MDSC ratio was increased and positively correlated with A_2BAR mRNA expression (r = 0.86, p < 0.01). In AMI model mice, the percentage of MDSCs was increased in the circulation and infarcted heart and decreased in the spleen. MRS-1754-mediated A_2BAR inhibition decreased the MDSC ratio in the circulation and infarcted heart and prevented the decrease in MDSC number in the spleens of mice with AMI. A_2BAR blockade inhibited myocardial cell apoptosis, alleviated myocardial inflammatory injury, and improved myocardial systolic function in the AMI mouse model. Similar results were found in mice after splenectomy. Additionally, spleen-derived MDSC injection increased the MDSC ratio in the infarcted heart, increased myocardial cell apoptosis, aggravated myocardial injury, and decreased cardiac systolic function in mice with AMI.

CONCLUSION

Blocking A_2BAR alleviates myocardial damage and improves myocardial systolic function through inhibition of spleen-derived MDSC mobilisation after AMI. Key MessagesSpleen-derived MDSC mobilisation aggravates myocardial inflammatory injury within 24 h of AMI.A_2BAR promotes spleen-derived MDSC mobilisation within 24 h of AMI.Blocking A_2BAR improves myocardial systolic function through inhibition of spleen-derived MDSC mobilisation.

Trend of Galectin-3 Levels in Patients with Non-ST-Elevation and ST-Elevation Myocardial Infarction

Background and Objectives: Given the fact that galectin-3 has a predictive significance on the development of myocardial dysfunction after acute myocardial infarction, the aim of our study was to examine potential factors that could be important for the dynamics of the concentration of this biomarker in the early postinfarction period. Materials and Methods: This study included 89 patients with a diagnosis of stable angina pectoris (SAP) or the first non-ST elevation (NSTEMI) or ST-elevation (STEMI) myocardial infarction, who underwent percutaneous coronary intervention (PCI). The study group included 23 patients with the first NSTEMI and 42 patients with STEMI, while the control group consisted of 24 patients with SAP hospitalized for elective PCI without a previous MI. All patients had preserved left ventricular ejection fraction. Galectin-3 levels were determined on days 1, 5, and 30 after PCI. The significance of various independent variables as predictors of galectin-3 concentration was analyzed after a series of univariate linear regression modeling in a multivariate linear regression model. Results: The average patients’ age was 63.99 ± 9.13 years. Statistically significantly higher values of C-reactive protein were established in STEMI compared to SAP (p < 0.01) or NSTEMI (p < 0.001), whereas WBC count was significantly lower in SAP than in STEMI (p < 0.001) and NSTEMI (p < 0.01) group. Although there were no statistically significant differences in measured galectin-3 concentrations between the examined groups on days 1, 5, and 30 after PCI, HTA, triglyceride level, LA size, treatment with trimetazidine and long-acting nitrates, as well as percentage of LM stenosis and E/A ratio were identified as independent predictors of galectin-3 concentration. Conclusions: In the post-MI period, very early values of galectin-3 correlate mostly with atherosclerosis factors, while on day 30 this biomarker correlates with diastolic dysfunction and “announces” left ventricular remodeling.