Biochemical Aspects That Lead to Abusive Use of Trimetazidine in Performance Athletes: A Mini-Review

Trimetazidine (TMZ), used for treating stable angina pectoris, has garnered attention in the realm of sports due to its potential performance-enhancing properties, and the World Anti-Doping Agency (WADA) has classified TMZ on the S4 list of prohibited substances since 2014. The purpose of this narrative mini-review is to emphasize the biochemical aspects underlying the abusive use of TMZ among athletes as a metabolic modulator of cardiac energy metabolism. The myocardium's ability to adapt its energy substrate utilization between glucose and fatty acids is crucial for maintaining cardiac function under various conditions, such as rest, moderate exercise, and intense effort. TMZ acts as a partial inhibitor of fatty acid oxidation by inhibiting 3-ketoacyl-CoA thiolase (KAT), shifting energy production from long-chain fatty acids to glucose, reducing oxygen consumption, improving cardiac function, and enhancing exercise capacity. Furthermore, TMZ modulates pyruvate dehydrogenase (PDH) activity, promoting glucose oxidation while lowering lactate production, and ultimately stabilizing myocardial function. TMZs role in reducing oxidative stress is notable, as it activates antioxidant enzymes like glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD). In conclusion, TMZs biochemical mechanisms make it an attractive but controversial option for athletes seeking a competitive edge.

Use of a gene expression signature to identify trimetazidine for repurposing to treat bipolar depression

OBJECTIVES

The aim of this study was to repurpose a drug for the treatment of bipolar depression.

METHODS

A gene expression signature representing the overall transcriptomic effects of a cocktail of drugs widely prescribed to treat bipolar disorder was generated using human neuronal-like (NT2-N) cells. A compound library of 960 approved, off-patent drugs were then screened to identify those drugs that affect transcription most similar to the effects of the bipolar depression drug cocktail. For mechanistic studies, peripheral blood mononuclear cells were obtained from a healthy subject and reprogrammed into induced pluripotent stem cells, which were then differentiated into co-cultured neurons and astrocytes. Efficacy studies were conducted in two animal models of depressive-like behaviours (Flinders Sensitive Line rats and social isolation with chronic restraint stress rats).

RESULTS

The screen identified trimetazidine as a potential drug for repurposing. Trimetazidine alters metabolic processes to increase ATP production, which is thought to be deficient in bipolar depression. We showed that trimetazidine increased mitochondrial respiration in cultured human neuronal-like cells. Transcriptomic analysis in induced pluripotent stem cell-derived neuron/astrocyte co-cultures suggested additional mechanisms of action via the focal adhesion and MAPK signalling pathways. In two different rodent models of depressive-like behaviours, trimetazidine exhibited antidepressant-like activity with reduced anhedonia and reduced immobility in the forced swim test.

CONCLUSION

Collectively our data support the repurposing of trimetazidine for the treatment of bipolar depression.

Evaluating the protective role of trimetazidine versus nano-trimetazidine in amelioration of bilateral renal ischemia/reperfusion induced neuro-degeneration: Implications of ERK1/2, JNK and Galectin-3 /NF-κB/TNF-α/HMGB-1 signaling

BACKGROUND

Renal ischemia/reperfusion (I/R) is a primary culprit of acute kidney injury. Neurodegeneration can result from I/R, but the mechanisms are still challenging. We studied the implications of bilateral renal I/R on brain and potential involvement of the oxidative stress (OS) driven extracellular signal-regulated kinase1/2, c-Jun N-terminal kinase (ERK1/2, JNK) and Galectin-3 (Gal-3)/nuclear factor Kappa B (NF-қB)/tumor necrosis factor-alpha (TNF-α), high mobility group box-1 (HMGB-1), and caspase-3 paths upregulation. We tested the impact of Nano-trimetazidine (Nano-TMZ) on these pathways being a target of its neuroprotective effects.

METHODS

Study groups; Sham, I/R, TMZ+I/R, and Nano-TMZ+I/R. Kidney functions, cognition, hippocampal OS markers, Gal-3, NF-қB, p65 and HMGB-1 gene expression, TNF-α level, t-JNK/p-JNK and t-ERK/p-ERK proteins, caspase-3, glial fibrillary acidic protein (GFAP) and ionized calcium binding protein-1 (Iba-1) were assessed.

RESULTS

Nano-TMZ averted renal I/R-induced hippocampal impairment by virtue of its anti: oxidative, inflammatory, and apoptotic properties.

CONCLUSION

Nano-TMZ is more than anti-ischemic.

Trimetazidine in heart failure with preserved ejection fraction: a randomized controlled cross-over trial

AIMS

Impaired myocardial energy homeostasis plays an import role in the pathophysiology of heart failure with preserved ejection fraction (HFpEF). Left ventricular relaxation has a high energy demand, and left ventricular diastolic dysfunction has been related to impaired energy homeostasis. This study investigated whether trimetazidine, a fatty acid oxidation inhibitor, could improve myocardial energy homeostasis and consequently improve exercise haemodynamics in patients with HFpEF.

METHODS AND RESULTS

The DoPING-HFpEF trial was a phase II single-centre, double-blind, placebo-controlled, randomized cross-over trial. Patients were randomized to trimetazidine treatment or placebo for 3 months and switched after a 2-week wash-out period. The primary endpoint was change in pulmonary capillary wedge pressure, measured with right heart catheterization at multiple stages of bicycling exercise. Secondary endpoint was change in myocardial phosphocreatine/adenosine triphosphate, an index of the myocardial energy status, measured with phosphorus-31 magnetic resonance spectroscopy. The study included 25 patients (10/15 males/females; mean (standard deviation) age, 66 (10) years; body mass index, 29.8 (4.5) kg/m2 ); with the diagnosis of HFpEF confirmed with (exercise) right heart catheterization either before or during the trial. There was no effect of trimetazidine on the primary outcome pulmonary capillary wedge pressure at multiple levels of exercise (mean change 0 [95% confidence interval, 95% CI -2, 2] mmHg over multiple levels of exercise, P = 0.60). Myocardial phosphocreatine/adenosine triphosphate in the trimetazidine arm was similar to placebo (1.08 [0.76, 1.76] vs. 1.30 [0.95, 1.86], P = 0.08). There was no change by trimetazidine compared with placebo in the exploratory parameters: 6-min walking distance (mean change of -6 [95% CI -18, 7] m vs. -5 [95% CI -22, 22] m, respectively, P = 0.93), N-terminal pro-B-type natriuretic peptide (5 (-156, 166) ng/L vs. -13 (-172, 147) ng/L, P = 0.70), overall quality-of-life (KCCQ and EQ-5D-5L, P = 0.78 and P = 0.51, respectively), parameters for diastolic function measured with echocardiography and cardiac magnetic resonance, or metabolic parameters.

CONCLUSIONS

Trimetazidine did not improve myocardial energy homeostasis and did not improve exercise haemodynamics in patients with HFpEF.

Antitumor effect of trimetazidine in a model of solid Ehrlich carcinoma is mediated by inhibition of glycolytic pathway and AKT signaling

Disturbance in glucose metabolism was proposed to be a pathogenetic mechanism of breast cancer. Trimetazidine (TMZ) inhibits β-oxidation of fatty acids through blocking the activity of 3-ketoacylCoA thiolase enzyme, leading to enhancement of glucose oxidation and metabolic respiration. The present study aimed to examine the cytotoxic effect of TMZ in both in vivo and in vitro models of breast cancer, focusing on its impact on the expression of some glycolytic enzymes and AKT signaling. The cytotoxic effect of TMZ was screened against breast (MCF-7) cancer cell line at different concentrations [0.01-100 μM]. In vivo, graded doses (10, 20, 30 mg/kg) of TMZ were tested against solid Ehrlich carcinoma (SEC) in mice. Tumor tissues were isolated for assessment of the expression of glucose transporter-1 (GLUT-1) and glycolytic enzymes by quantitative PCR. The protein expression of AKT and cellular myelocytomatosis (c-Myc) was determined by western blotting, while p53 expression was evaluated by immunohistochemistry. Molecular docking study of TMZ effect on AKT and c-Myc was performed using Auto-Dock Vina docking program. TMZ showed a cytotoxic action against MCF-7 cells, having IC50 value of 2.95 μM. In vivo, TMZ reduced tumor weight, downregulated the expression of glycolytic enzymes, suppressed AKT signaling, but increased p53 expression. Molecular docking and in silico studies proposed that TMZ is an AKT and c-Myc selective inhibitor. In conclusion, TMZ demonstrated a viable approach to suppress tumor proliferation in biological models of breast cancer.

Insights into the therapeutic outcomes of trimetazidine/doxorubicin combination in Ehrlich solid-phase carcinoma mouse tumor model

One of the key features of cancer is metabolic reprogramming that can be exploited to sensitize cancer cells to chemotherapy. Trimetazidine (TMZ) is a metabolic anti-ischemic drug that blocks the activity of long-chain 3-ketoacyl CoA thiolase leading to the inhibition of fatty acid oxidation.

AIMS

The objective of the current investigation was to evaluate the idea that TMZ could synergize the antitumor activity of doxorubicin (DOX).

MAIN METHODS

The hypothesis was examined in vitro using the human breast cancer cell lines MCF-7 and MDA-MB231. In addition, the in vivo experiments were conducted using the Ehrlich solid phase carcinoma model.

KEY FINDINGS

In vitro cytotoxicity experiments demonstrated that TMZ improved the potency of DOX in MCF-7 cell lines in a synergistic manner. In vivo testing confirmed that DOX/TMZ combination exhibits synergistic effect at both DOX/TMZ 1:10 and 1:5 ratios, where DOX was administered at one tenth and one fifth of its original dose, respectively. The co-treatment (1:5 ratio) significantly reduced tumor Nicotinamide adenine dinucleotide (NAD)+/NADH ratio (6.1-fold) and Adenosine triphosphate (ATP) levels (61 %) with concurrent activation of AMP-activated protein kinase (AMPK) (2.2-fold) and peroxisome proliferator-activated receptor-gamma coactivator (PGC)1-α (5.5-fold) protein expression versus control. The same treatment decreased the nuclear levels of NF-κB (p65) (57.5 %) and induced tumor apoptosis as evidenced by elevated Bax/Bcl-2 ratio (6.8-fold) along with active caspase-3 levels (6.6-fold) against control.

SIGNIFICANCE

The current investigation constitutes a proof-of-concept study that provided preclinical evidence for the anticancer activity of DOX/TMZ combination and warrants further investigation for repurposing TMZ in DOX protocols.

Neuroprotective potential of trimetazidine against tramadol-induced neurotoxicity: role of PI3K/Akt/mTOR signaling pathways

Tramadol (TRA) causes neurotoxicity whereas trimetazidine (TMZ) is neuroprotective. The potential involvement of the PI3K/Akt/mTOR signaling pathway in the neuroprotection of TMZ against TRA-induced neurotoxicity was evaluated. Seventy male Wistar rats were divided into groups. Groups 1 and 2 received saline or TRA (50 mg/kg). Groups 3, 4, and 5 received TRA (50 mg/kg) and TMZ (40, 80, or 160 mg/kg) for 14 days. Group 6 received TMZ (160 mg/kg). Hippocampal neurodegenerative, mitochondrial quadruple complex enzymes, phosphatidylinositol-3-kinases (PI3Ks)/protein kinase B levels, oxidative stress, inflammatory, apoptosis, autophagy, and histopathology were evaluated. TMZ decreased anxiety and depressive-like behavior induced by TRA. TMZ in tramadol-treated animals inhibited lipid peroxidation, GSSG, TNF-α, and IL-1β while increasing GSH, SOD, GPx, GR, and mitochondrial quadruple complex enzymes in the hippocampus. TRA inhibited Glial fibrillary acidic protein expression and increased pyruvate dehydrogenase levels. TMZ reduced these changes. TRA decreased the level of JNK and increased Beclin-1 and Bax. TMZ decreased phosphorylated Bcl-2 while increasing the unphosphorylated form in tramadol-treated rats. TMZ activated phosphorylated PI3Ks, Akt, and mTOR proteins. TMZ inhibited tramadol-induced neurotoxicity by modulating the PI3K/Akt/mTOR signaling pathways and its downstream inflammatory, apoptosis, and autophagy-related cascades.

The application of trimetazidine in healthy individuals: a systematic review

OBJECTIVE

Currently, there is no evidence to support trimetazidine (TMZ) administration aimed at enhancing physical performance or post-exercise recovery in healthy individuals or athletes from the general and athletic populations, respectively. Considering the lack of empirical data, from a scientific and practical perspective, it would be interesting to review research with high methodological quality that examines the effects of TMZ on healthy individuals and athletes from various age groups.

MATERIALS AND METHODS

Data sources included English articles that were initially searched by keywords utilizing PubMed, Scopus databases, and the Cochrane Library and published prior to November 2022. Thus, a systematic review of the scientific literature was performed with a traditional PRISMA methodology. An initial keyword search found 2,673 publications, and further screening selected 66 articles, of which only two articles met the inclusion criteria.

RESULTS

Two trials examining the effect of TMZ on healthy members of the general population that were published in 2017 and 2019 were analyzed. Publications examining athletes were not recruited for this analysis.

CONCLUSIONS

Currently, there are no data reporting a positive effect of TMZ on physical performance, post-exercise recovery, or other health parameters in members of the general population, while its administration is associated with the development of relatively common adverse effects.

Regulatory effects of trimetazidine in cardiac ischemia/reperfusion injury

Ischemia/reperfusion (I/R) injury is a tissue damage during reperfusion after an ischemic condition. I/R injury is induced by pathological cases including stroke, myocardial infarction, circulatory arrest, sickle cell disease, acute kidney injury, trauma, and sleep apnea. It can lead to increased morbidity and mortality in the context of these processes. Mitochondrial dysfunction is one of the hallmarks of I/R insult, which is induced via reactive oxygen species (ROS) production, apoptosis, and autophagy. MicroRNAs (miRNAs, miRs) are non-coding RNAs that play a main regulatory role in gene expression. Recently, there are evidence, which miRNAs are the major modulators of cardiovascular diseases, especially myocardial I/R injury. Cardiovascular miRNAs, specifically miR-21, and probably miR-24 and miR-126 have protective effects on myocardial I/R injury. Trimetazidine (TMZ) is a new class of metabolic agents with an anti-ischemic activity. It has beneficial effects on chronic stable angina by suppressing mitochondrial permeability transition pore (mPTP) opening. The present review study addressed the different mechanistic effects of TMZ on cardiac I/R injury. Online databases including Scopus, PubMed, Web of Science, and Cochrane library were assessed for published studies between 1986 and 2021. TMZ, an antioxidant and metabolic agent, prevents the cardiac reperfusion injury by regulating AMP-activated protein kinase (AMPK), cystathionine-γ-lyase enzyme (CSE)/hydrogen sulfide (H2S), and miR-21. Therefore, TMZ protects the heart against I/R injury by inducing key regulators such as AMPK, CSE/H2S, and miR-21.

Trimetazidine Affects Mitochondrial Calcium Uniporter Expression to Restore Ischemic Heart Function via Reactive Oxygen Species/NFκB Pathway Inhibition

ABSTRACT

Studies have demonstrated the roles of trimetazidine beyond being an antianginal agent in ischemic heart disease (IHD) treatment associated with mechanisms of calcium regulation. Our recent studies revealed that mitochondrial calcium uniporter (MCU, the pore-forming unit responsible for mitochondrial calcium entrance) inhibition provided cardioprotective effects for failing hearts. Because trimetazidine and MCU are associated with calcium homeostasis, we hypothesized that trimetazidine may affect MCU to restore the failing heart function. In the present study, we tested this hypothesis in the context of cardiac ischemia in vivo and in vitro. The IHD model was established in male C57BL/6 mice followed by trimetazidine administration intraperitoneally at 20 mg/kg q.o.d for 8 weeks. In vitro studies were performed in a hypoxia model using primary rat neonate cardiomyocytes. The mice survival outcomes and heart function, pathohistologic, and biological changes were analyzed. The results demonstrated that trimetazidine treatment resulted in longer life spans and heart function improvement accompanied by restoration of mitochondrial calcium levels and increase in ATP production via MCU down-regulation. Studies in vitro further showed that trimetazidine treatment and MCU inhibition decreased reactive oxygen species (ROS) production, inhibited the NFκB pathway, and protected the cardiomyocytes from hypoxic injury, and vice versa. Thus, the present study unveils a unique mechanism in which trimetazidine is involved in ameliorating the ischemic failing heart via MCU down-regulation and the following mitochondrial calcium homeostasis restoration, ROS reduction, and cardiomyocyte protection through NFκB pathway inhibition. This mechanism provides a novel explanation for the treatment effects of trimetazidine on IHD.

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.

Trimetazidine provides protection against diabetic polyneuropathy in rats via modulation of soluble HMGB1

OBJECTIVE

The aim of this study was to evaluate the neuroprotective efficacy of trimetazidine (TMZ) in a diabetic neuropathy model of the sciatic nerve.

MATERIALS AND METHODS

We performed intraperitoneal (IP) single-dose streptozotocin (STZ) injection for a diabetes mellitus neuropathy model in 24 rats; 8 rats were in the control group, and no chemical administration was performed. 24 diabetic rats were randomly divided into 3 groups: Group 1 rats (n = 8; diabetes and saline groups) were given 1 ml/kg saline treatment. Diabetes and trimetazidine (TMZ)-treated rats (n = 8) were given TMZ 10 mg/kg/day i.p. in Group 2. Group 3 rats were given TMZ 20 mg/kg/day by i.p. for 4 weeks. At the end of the study, EMG and inclined plane testing were used, and blood samples were taken.

RESULTS

Amplitudes of CMAP increased significantly in the TMZ treatment group when compared with the group that had been given saline treatment. The latency of CMAP was significantly shortened in the TMZ treatment group as compared to the saline treatment group. When compared to the saline treatment group, 10 mg/kg and 20 mg/kg TMZ treatment significantly reduced HMGB1, Pentraxin-3, TGF-beta, and MDA levels.

CONCLUSIONS

We demonstrated the neuroprotective effect of TMZ on diabetic polyneuropathy in rats via modulation of soluble HMGB1.

Trimetazidine enhances myocardial angiogenesis in pressure overload-induced cardiac hypertrophy mice through directly activating Akt and promoting the binding of HSF1 to VEGF-A promoter

Latest clinical research shows that trimetazidine therapy during the perioperative period relieves endothelial dysfunction in patients with unstable angina induced by percutaneous coronary intervention. In this study we investigated the effects of TMZ on myocardial angiogenesis in pressure overload-induced cardiac hypertrophy mice. Cardiac hypertrophy was induced in mice by transverse aortic constriction (TAC) surgery. TAC mice were administered trimetazidine (2.8 mg/100 µL, i.g.) for 28 consecutive days. We showed that trimetazidine administration significantly increased blood vessel density in the left ventricular myocardium and abrogated cardiac dysfunction in TAC mice. Co-administration of a specific HSF1 inhibitor KRIBB11 (1.25 mg/100 µL, i.h.) abrogated the angiogenesis-promoting effects of trimetazidine in TAC mice. Using luciferase reporter and electrophoretic mobility shift assays we demonstrated that the transcription factor HSF1 bound to the promoter region of VEGF-A, and the transcriptional activity of HSF1 was enhanced upon trimetazidine treatment. In molecular docking analysis we found that trimetazidine directly bound to Akt via a hydrogen bond with Asp292 and a pi-pi bond with Trp80. In norepinephrine-treated HUVECs, we showed that trimetazidine significantly increased the phosphorylation of Akt and the synergistic nuclear translocation of Akt and HSF1, as well as the binding of Akt and HSF1 in the nucleus. These results suggest that trimetazidine enhances myocardial angiogenesis through a direct interaction with Akt and promotion of nuclear translocation of HSF1, and that trimetazidine may be used for the treatment of myocardial angiogenic disorders in hypertensive patients.

Trimetazidine, an Anti-Ischemic Drug, Reduces the Antielectroshock Effects of Certain First-Generation Antiepileptic Drugs

Trimetazidine (TMZ), an anti-ischemic drug for improving cellular metabolism, is mostly administered to patients with poorly controlled ischemic heart disease (IHD). Since IHD is considered the most frequent causative factor of cardiac arrhythmias, and these often coexist with seizure disorders, we decided to investigate the effect of TMZ in the electroconvulsive threshold test (ECT) and its influence on the action of four first-generation antiepileptic drugs in the maximal electroshock test (MES) in mice. The TMZ (up to 120 mg/kg) did not affect the ECT, but applied at doses of 20–120 mg/kg it decreased the antielectroshock action of phenobarbital. The TMZ (50–120 mg/kg) reduced the effect of phenytoin, and, when administered at a dose of 120 mg/kg, it diminished the action of carbamazepine. All of these revealed interactions seem to be pharmacodynamic, since the TMZ did not affect the brain levels of antiepileptic drugs. Furthermore, the combination of TMZ with valproate (but not with other antiepileptic drugs) significantly impaired motor coordination, evaluated using the chimney test. Long-term memory, assessed with a passive-avoidance task, was not affected by either the TMZ or its combinations with antiepileptic drugs. The obtained results suggest that TMZ may not be beneficial as an add-on therapy in patients with IHD and epilepsy.

Trimetazidine Reduces Cardiac Fibrosis in Rats by Inhibiting NOX2-Mediated Endothelial-to-Mesenchymal Transition

Purpose

Methods

Results

Conclusion

Trimetazidine Effect on the Cardiac Autonomic Nerve System after Percutaneous Coronary Intervention in Coronary Heart Disease: A Propensity-score Matched Study

OBJECTIVE

To assess the effects of trimetazidine (TMZ) added to conventional drug therapy on cardiac autonomic nervous CANS in patients with coronary heart disease (CHD) after the percutaneous coronary intervention (PCI).

STUDY DESIGN

Descriptive study.

PLACE AND DURATION OF STUDY

 Department of Cardiology, The Second Hospital of Hebei Medical University, Hebei, China, from May 2018 to September 2019.

METHODOLOGY

The study included 50 patients with CHD after a successful PCI who received trimetazidine plus conventional therapy were included as cases (exposed group), and 50 matched patients were identified as controls (non-exposed group). Heart rate (HR) and heart rate variability (HRV) parameters including sympathetic activity (SDNN, LF), parasympathetic activity (RMSSD, pNN50, SDSD, HF), and sympathovagal balance (LF/HF ratio) were used to evaluate CANS function.

RESULTS

There were no statistical differences in the HR and HRV parameters before and after PCI (p>0.05). In the non-exposed group, conventional therapy significantly improved the HRV parameters (all p<0.05), while not affecting HR (p>0.05). In the exposed group, all HRV parameters except HR were improved after 4 weeks of treatment. After 4 weeks of treatment, the exposed group had higher parasympathetic-nerve activity, lower sympathetic-nerve activity, and LF/HF ratio compared to the non-exposed group (all p<0.05).

CONCLUSIONS

The application of TMZ based on conventional therapy effectively improved the CANS in CHD patients who underwent PCI.

KEY WORDS

Coronary heart disease, Percutaneous coronary intervention, Trimetazidine, Cardiac autonomic nervous system, Heart rate variability.

Trimetazidine Alleviates Postresuscitation Myocardial Dysfunction and Improves 96-Hour Survival in a Ventricular Fibrillation Rat Model

Background Myocardial dysfunction is a critical cause of post-cardiac arrest hemodynamic instability and circulatory failure that may lead to early mortality after resuscitation. Trimetazidine is a metabolic agent that has been demonstrated to provide protective effects in myocardial ischemia. However, whether trimetazidine protects against postresuscitation myocardial dysfunction is unknown. Methods and Results Cardiopulmonary resuscitation was initiated after 8 minutes of untreated ventricular fibrillation in Sprague-Dawley rats. Animals were randomized to 4 groups immediately after resuscitation (n=15/group): (1) normothermia control (NTC); (2) targeted temperature management; (3) trimetazidine-normothermia; (4) trimetazidine-targeted temperature management. TMZ was administered at a single dose of 10 mg/kg in rats with trimetazidine. The body temperature was maintained at 34.0°C for 2 hours and then rewarmed to 37.5°C in rats with targeted temperature management. Postresuscitation hemodynamics, 96-hours survival, and pathological analysis were assessed. Heart tissues and blood samples of additional rats (n=6/group) undergoing the same experimental procedure were collected to measure myocardial injury, inflammation and oxidative stress-related biomarkers with ELISA-based quantification assays. Compared with normothermia control, tumor necrosis factor-α, and cardiac troponin-I were significantly reduced, whereas the left ventricular ejection fraction and 96-hours survival rates were significantly improved in the 3 experimental groups. Furthermore, inflammation and oxidative stress-related biomarkers together with collagen volume fraction were significantly decreased in rats undergoing postresuscitation interventions. Conclusions Trimetazidine significantly alleviates postresuscitation myocardial dysfunction and improves survival by decreasing oxidative stress and inflammation in a ventricular fibrillation rat model. A single dose of trimetazidine administrated immediately after resuscitation can effectively improve cardiac function, whether used alone or combined with targeted temperature management.

Trimetazidine and exercise offer analogous improvements to the skeletal muscle insulin resistance of mice through Nrf2 signaling

INTRODUCTION

Insulin resistance (IR) plays a key role in the pathogenesis and clinical course of patients with multiple metabolic diseases and diabetes. This study aimed to explore the effect of trimetazidine (TMZ) on skeletal muscle IR in mice fed a high-fat diet (HFD) and explore the possible underlying mechanism.

RESEARCH DESIGN AND METHODS

In vivo, a HFD mouse IR model was adopted and TMZ and exercise were used to intervene. Postintervention the following were determined: blood levels of glucose and insulin, homeostasis model assessment of IR index, expression of skeletal muscle insulin signaling-related proteins phosphorylated insulin receptor substrate 1 (p-IRS1/IRS1) and phosphorylated protein kinase B (p-AKT/AKT), nuclear factor erythroid 2 related factor 2 (Nrf2) signaling pathway, and oxidative stress. In vitro, a palmitate-treated C2C12 myotube IR model was constructed. Cellular glucose uptake, p-IRS1/IRS1, and p-AKT/AKT were determined, and reactive oxygen species (ROS) production was analyzed based on treatments with specific small interfering RNA of Nrf2 with or without TMZ. Western blot was used to obtain the protein expression level and ROS production by functional analysis kits.

RESULTS

In vivo, TMZ and exercise decreased the blood glucose and insulin levels and homeostasis model assessment of IR index, increased skeletal muscle insulin signaling-related protein ratios of p-IRS1/IRS1 and p-AKT/AKT, and both interventions activated Nrf2 signaling and reduced oxidative stress production in HFD mice. In vitro, TMZ reduced the oxidative stress reaction, increased the ratios of p-AKT/AKT and p-IRS1/IRS1, and attenuated the insulin stimulation of PA-induced glucose uptake. However, in the absence of Nrf2, TMZ failed to resist the effects of IR.

CONCLUSIONS

This study showed that TMZ, like exercise, brought about marked improvements to HFD-induced skeletal muscle IR through TMZ, a common pathway with exercise in the form of Nrf2, regulating oxidative stress. We provide new evidence to support the use of TMZ for diabetes treatment.

Trimetazidine ameliorates hindlimb ischaemic damage in type 2 diabetic mice

BACKGROUND

Ischaemia caused by lower extremity artery stenosis is the main cause of peripheral artery disease (PAD) in patients with diabetes. Trimetazidine (TMZ) has traditionally been used as an anti-ischaemic drug for coronary artery disease. The effect of TMZ on PAD in a diabetic animal model and the underlying molecular mechanisms remain unclear.

METHODS

The db/db mice were challenged with femoral artery ligation (FAL), followed by TMZ treatment for 2 weeks. Scores on hindlimb ischaemia and function were evaluated. Histological and capillary density analyses of gastrocnemius were performed. The expression of vascular endothelial growth factor (VEGF) and myogenic regulators was also confirmed by Western blotting. We also detected serum intercellular adhesion molecule 1 (ICAM-1) level through ELISA.

RESULTS

Diabetic mice exhibited limb ulceration and motor dysfunction after FAL while TMZ-treated db/db mice exhibited milder ischaemic impairment. Furthermore, decreased capillary density in the gastrocnemius muscles of ischaemic hindlimb and reduced expressions of VEGF, myogenic markers, and serum ICAM-1 could be partially reversed by TMZ treatment.

CONCLUSION

TMZ may alleviate hindlimb ischaemic damage in db/db mice, at least partly, through enhancing angiogenesis and promoting myogenesis in ischaemia region.Key messagesTMZ intervention could alleviate hindlimb ischaemic damage in db/db mice.TMZ intervention could enhance angiogenesis and stimulate myogenesis in ischaemia region.

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

OBJECTIVE

To study the protective effect of trimetazidine on myocardial cells in rats with myocardial infarction and explore its effect on ERK signaling pathway.

METHODS

40 SD rats were randomly divided into the sham operation group, model group, low-dose group, and high-dose group (intra-abdominal injection of trimetazidine 5 mg/kg and 10 mg/kg, respectively), construction of rat myocardial infarction model by coronary artery left anterior descending artery ligation. 7 days after surgery, the survival rate and cardiac function of each group of rats were recorded. The myocardial infarct size was detected by TTC staining. The apoptosis level of rat cardiomyocytes was detected by TUNEL staining. The content of ROS in rat cardiomyocytes was detected by DCFH-DA. Western-blot was used to detection of Caspase-3, Bcl-2/Bax, and ERK signaling pathway-related proteins in myocardial tissue.

RESULTS

Compared with the model group, the survival rate of the rats in the low-dose group and the high-dose group was significantly increased (P < 0.01), the cardiac function was significantly improved (P < 0.01), the myocardial infarct size was significantly decreased (P < 0.01), the level of apoptosis was significantly decreased (P < 0.01), the content of ROS in cardiomyocytes was significantly decreased (P < 0.01), the protein expression of Caspase-3 and NF-κB in cardiomyocytes was significantly decreased (P < 0.01), and the expression of Bcl-2/Bax and p-ERK were significantly increased (P < 0.01).

CONCLUSION

Trimetazidine can activate ERK signaling pathway in cardiomyocytes of rats with myocardial infarction, increase the expression of p-ERK, decrease the content of ROS in cardiomyocytes, decrease the expression of apoptotic proteins, reduce myocardial infarct size, improve cardiac function, and increase myocardial function.

Trimetazidine Protects from Mercury-Induced Kidney Injury

INTRODUCTION

The presence of mercury in the environment is a worldwide concern. Inorganic mercury is present in industrial materials, is employed in medical devices, is widely used in batteries, is a component of fluorescent light bulbs, and it has been associated with human poisoning in gold mining areas. The nephrotoxicity induced by inorganic mercury is a relevant health problem mainly in developing countries. The primary mechanism of mercury toxicity is oxidative stress. Trimetazidine (TMZ) is an anti-ischemic drug, which inhibits cellular oxidative stress, eliminates oxygen-free radicals, and improves lipid metabolism. The aim of this study was to evaluate whether the administration of TMZ protects against mercuric chloride (HgCl2) kidney damage.

METHODS

Adult male Wistar rats received only HgCl2 (4 mg/kg bw, sc) (Hg group, n = 5) or TMZ (3 mg/kg bw, ip) 30 min before HgCl2 administration (4 mg/kg bw, sc) (TMZHg group, n = 7). Simultaneously, a control group of rats (n = 4) was studied. After 4 days of HgCl2 injection, urinary flow, urea and creatinine (Cr) plasma levels, Cr clearance, urinary glucose, and sodium-dicarboxylate cotransporter 1 (NaDC1) in urine were determined. Lipid peroxidation (MDA) and glutathione (GSH) levels were measured in kidney homogenates.

RESULTS

Rats only treated with HgCl2 showed an increase in urea and Cr plasma levels, urinary flow, fractional excretion of water, glucosuria, and NaDC1 urinary excretion as compared with the control group and a decrease in Cr clearance. TMZHg group showed a decrease in urea and Cr plasma levels, urinary flow, fractional excretion of water, glucosuria, NaDC1 urinary excretion, and an increase in Cr clearance when compared to the Hg group. Moreover, MDA and GSH levels observed in Hg groups were decreased and increased, respectively, by TMZ pretreatment.

CONCLUSION

TMZ exerted a renoprotective action against HgCl2-induced renal injury, which might be mediated by the reduction of oxidative stress. Considering the absence of toxicity of TMZ, its clinical application against oxidative damage due to HgCl2-induced renal injury should be considered. The fact that TMZ is commercially available should simplify and accelerate the translation of the present data "from bench to bedside." In this context, TMZ become an interesting new example of drug repurposing.

Inhibiting Cardiac Mitochondrial Fatty Acid Oxidation Attenuates Myocardial Injury in a Rat Model of Cardiac Arrest

Mitochondrial fatty acid oxidation (FAO) is involved in myocardial damage after cardiopulmonary resuscitation (CPR). This study is aimed at investigating the effect of inhibiting mitochondrial FAO on myocardial injury and the underlying mechanisms of postresuscitation myocardial dysfunction. Rats were induced, subjected to 8 min of ventricular fibrillation, and underwent 6 min of CPR. Rats with return of spontaneous circulation (ROSC) were randomly divided into the Sham group, CPR group, and CPR + Trimetazidine (TMZ) group. Rats in the CPR + TMZ group were administered TMZ (10 mg/kg) at the onset of ROSC via the right external jugular vein, while rats in the CPR group were injected with equivalent volumes of vehicle. The sham rats were only administered equivalent volumes of vehicle. We found that the activities of enzymes related to cardiac mitochondrial FAO were partly improved after ROSC. TMZ, as a reversible inhibitor of 3-ketoacyl CoA thiolase, inhibited myocardial mitochondrial FAO after ROSC. In the CPR + TMZ group, the levels of mitochondrial injury in cardiac tissue were alleviated following attenuated myocardial damage and oxidative stress after ROSC. In addition, the disorder of cardiac mitochondrial metabolism was ameliorated, and specifically, the superfluous succinate related to mitochondrial reactive oxygen species (ROS) generation was decreased by inhibiting myocardial mitochondrial FAO with TMZ administration after ROSC. In conclusion, in the early period after ROSC, inhibiting cardiac mitochondrial FAO attenuated excessive cardiac ROS generation and preserved myocardial function, probably by alleviating the dysfunction of cardiac mitochondrial metabolism in a rat model of cardiac arrest.

Effect of trimetazidine on incidence of major adverse cardiac events in coronary artery disease patients undergoing percutaneous coronary intervention: A protocol for systematic review and meta-analysis

BACKGROUND

Percutaneous coronary intervention (PCI) is a common treatment method for coronary artery disease (CAD). PCI can cause myocardial ischemia or injury, and lead to major adverse cardiac events (MACEs). Trimetazidine has significant cardioprotective effects and improves endothelial dysfunction and myocardial injury. We will conduct a comprehensive systematic review and meta-analysis to evaluate effect of trimetazidine on incidence of MACE in CAD patients undergoing PCI.

METHODS

PubMed, Embase, Web of Science, Cochrane Library, the China National Knowledge Infrastructure, Chinese Biomedical Literature Database, and China Science and Technology Journal Database will be searched to collect randomized controlled trials (RCTs) of trimetazidine for CAD patients undergoing PCI. The range of publication time will be from the inception of the database to October 2020 without language limitation. Two reviewers will independently conduct study selection, data extraction and management, and assessment of risk of bias. Any disagreement will be resolved by discussion with the third reviewer. Review Manager Software 5.3 will be used for meta-analysis. The Cochrane risk of bias tool will be used to assess the risk of bias.

RESULTS

This study will provide a systematic synthesis of current published data to summarize the effect of trimetazidine on incidence of MACE such as stent restenosis, stent thrombosis, new significant coronary stenosis, myocardial infarction, heart failure, and cardiac arrest in CAD patients undergoing PCI.

CONCLUSIONS

This meta-analysis will provide evidence as to whether trimetazidine can reduce incidence of MACE in CAD patients undergoing PCI.

STUDY REGISTRATION NUMBER

INPLASY202090083.

Protective effect of trimetazidine in radiation-induced cardiac fibrosis in mice

Radiation-induced heart damage is a serious side effect caused by radiotherapy, especially during the treatment of cancer near the chest. Trimetazidine is effective at reducing inflammation in the heart, but how it affects radiation-induced cardiac fibrosis (RICF) is unknown. To investigate the potential effect and molecular mechanism, we designed this project with a C57BL6 male mouse model supposing trimetazidine could inhibit RICF in mice. During the experiment, mice were randomly divided into six groups including a control group (Con), radiation-damaged model group (Mod) and four experimental groups receiving low-dose (10 mg/kg/day) or high-dose (20 mg/kg/day) trimetazidine before or after radiation treatment. Apart from the control group, all mice chests were exposed to 6 MV X-rays at a single dose of 20 Gy to induce RICF, and tissue analysis was done at 8 weeks after irradiation. Fibroblast or interstitial tissues and cardiac fibrosis-like characteristics were determined using haematoxylin and eosin and Masson staining, which can be used to assess myocardial fibrosis. Immunohistochemical analysis and RT-PCR were used to determine gene expression and study the molecular mechanism. As a result, this study suggests that trimetazidine inhibits RICF by reducing gene expression related to myocyte apoptosis and fibrosis formation, i.e. connective tissue growth factor (CTGF), transforming growth factor (TGF)-β1, smad2 and smad3. In conclusion, by regulating the CTGF/TGF-β1/Smad pathway, trimetazidine could be a prospective drug for clinical treatment of RICF.

Inhibition of Fatty Acid Oxidation Promotes Macrophage Control of Mycobacterium tuberculosis

Macrophage activation involves metabolic reprogramming to support antimicrobial cellular functions. How these metabolic shifts influence the outcome of infection by intracellular pathogens remains incompletely understood. Mycobacterium tuberculosis (Mtb) modulates host metabolic pathways and utilizes host nutrients, including cholesterol and fatty acids, to survive within macrophages. We found that intracellular growth of Mtb depends on host fatty acid catabolism: when host fatty acid β-oxidation (FAO) was blocked chemically with trimetazidine, a compound in clinical use, or genetically by deletion of the mitochondrial fatty acid transporter carnitine palmitoyltransferase 2 (CPT2), Mtb failed to grow in macrophages, and its growth was attenuated in mice. Mechanistic studies support a model in which inhibition of FAO generates mitochondrial reactive oxygen species, which enhance macrophage NADPH oxidase and xenophagy activity to better control Mtb infection. Thus, FAO inhibition promotes key antimicrobial functions of macrophages and overcomes immune evasion mechanisms of Mtb.IMPORTANCEMycobacterium tuberculosis (Mtb) is the leading infectious disease killer worldwide. We discovered that intracellular Mtb fails to grow in macrophages in which fatty acid β-oxidation (FAO) is blocked. Macrophages treated with FAO inhibitors rapidly generate a burst of mitochondria-derived reactive oxygen species, which promotes NADPH oxidase recruitment and autophagy to limit the growth of Mtb. Furthermore, we demonstrate the ability of trimetazidine to reduce pathogen burden in mice infected with Mtb. These studies will add to the knowledge of how host metabolism modulates Mtb infection outcomes.

Protective Effects Of Trimetazidine Against Doxorubicin-Induced Cardiotoxicity And Hepatotoxicity In Mice

BACKGROUND

Trimetazidine (TMZ) is traditionally known for cardio protection, however various experimental studies are also evaluating its protective benefits in other tissues. Doxorubicin (DOX) is an extensively used chemotherapeutic drug but is associated with a high incidence of multi-organ damage. This study was aimed at countering DOX induced cardiac and hepatic toxicity by administering TMZ in two different study designs.

METHODS

It was a laboratory based randomized controlled trial conducted on 40 BALB/c mice divided into 5 groups (n=8). In the two study designs conducted, TMZ in a dose of 10 mg/kg was given orally for five and ten consecutive days. On the third and eighth day of the respective designs, 10 mg/kg DOX was administered intraperitoneally.

RESULTS

DOX induced significant elevation of four biochemical markers, namely creatine kinase MB (CKMB), lactate dehydrogenase (LDH), alanine aminotransferase (ALT) and aspartate aminotransferase (AST) (p-value ≤0.0001). Histological changes in heart were graded to be moderate while hepatic changes were graded as mild. Trimetazidine administration for ten days attenuated the enzyme upsurge significantly with p-value ≤0.05 for ALT and ≤0.0001 for AST, LDH and CKMB. However, five-day TMZ administration caused nonsignificant restoration in ALT and CKMB level (p-value >0.05). Hepatic and cardiac histological changes were restored accordingly in both groups.

CONCLUSIONS

Treatment with TMZ for ten days, seven of which were prior to DOX administration, was concluded to be an effective strategy to counter cardiac and hepatic toxicity of DOX.

Effect of trimetazidine combined with perindopril on NT-proBNP level in rats with dilated cardiomyopathy

This experiment aimed to study the effect of trimetazidine combined with perindopril on NT-proBNP levels in rats with dilated cardiomyopathy (DCM). 40 SD rats were selected and 10 rats were randomly selected to continue to be fed as the blank group. The other 30 rats were injected with adriamycin to establish the DCM rat model. Then they were divided into 3 groups, namely control group (without any drug intervention), trimetazidine group (with trimetazidine single-agent intervention) and combination drug group (with trimetazidine combined with perindopril intervention), with 10 DCM rats in each group. After 4 weeks of intervention, left ventricular ejection fraction (LVEF), left ventricular end-diastolic dimension (LVEDD) and left ventricular end-systolic diameter (LVESD) of rats were measured by echocardiography. The changes of plasma brain natriuretic peptide (BNP) level and n-terminal pro-brain natriuretic peptide (NT-proBNP) were detected by ELISA. RT-PCR was used to detect the regulation of angiotensin II type 1 receptor (AT1Rs) and lamin A mRNA expression in rat myocardium. After the intervention, the LVEF%, LVEDD and LVESD measured values of the rats in the combination drug group were significantly better than those in the trimetazidine group and the control group (P&lt; 0.05). The BNP, NT-proBNP and AT1Rs levels of the rats in the combination drug group were significantly lower than those in the trimetazidine group and the control group. The difference was statistically significant (p&lt; 0.05). The lamin A expression of the rats in the combination drug group was significantly higher than that in the trimetazidine group and the control group. The difference was statistically significant (P&lt; 0.05). Compared with trimetazidine single-agent, trimetazidine combined with perindopril can significantly improve the cardiac function of rats with dilated cardiomyopathy, reduce the serum NT-proBNP level and improve the expression of AT1Rs and lamin A in rats.

Functional analysis of molecular and pharmacological modulators of mitochondrial fatty acid oxidation

Fatty acid oxidation (FAO) is a key bioenergetic pathway often dysregulated in diseases. The current knowledge on FAO regulators in mammalian cells is limited and sometimes controversial. Previous FAO analyses involve nonphysiological culture conditions or lack adequate quantification. We herein described a convenient and quantitative assay to monitor dynamic FAO activities of mammalian cells in physiologically relevant settings. The method enabled us to assess various molecular and pharmacological modulators of the FAO pathway in established cell lines, primary cells and mice. Surprisingly, many previously proposed FAO inhibitors such as ranolazine and trimetazidine lacked FAO-interfering activity. In comparison, etomoxir at low micromolar concentrations was sufficient to saturate its target proteins and to block cellular FAO function. Oxfenicine, on the other hand, acted as a partial inhibitor of FAO. As another class of FAO inhibitors that transcriptionally repress FAO genes, antagonists of peroxisome proliferator-activated receptors (PPARs), particularly that of PPARα, significantly decreased cellular FAO activity. Our assay also had sufficient sensitivity to monitor upregulation of FAO in response to environmental glucose depletion and other energy-demanding cues. Altogether this study provided a reliable FAO assay and a clear picture of biological properties of potential FAO modulators in the mammalian system.

Protective effects of naringin and trimetazidine on remote effect of acute renal injury on oxidative stress and myocardial injury through Nrf-2 regulation

BACKGROUND

Ischemia/reperfusion (I/R) is the predominant cause of acute renal failure (ARF), which damages the remote organs, especially the heart, and subsequently leads to death. The aim of the current study was to examine the effects of naringin (NAR), trimetazidine (TMZ), or their combination on the Nrf-2 expression in the kidney tissue, and myocardial injury in the renal IR injury in rats.

METHODS

Forty male Sprague-Dawley rats were randomly separated into five groups as follows: sham, IR injury, TMZ (5 mg/kg, intravenously), NAR (100 mg/kg), and their combination. Renal I/R injury and ischemia were induced by using clamps for 45 min, and after 4 h reperfusion, respectively. Then, the Nrf-2 expression in the kidney, antioxidant activity (CAT, SOD, and GPx), total antioxidant capacity (TAC), oxidative stress, electrocardiogram (ECG) parameters, and biochemical markers were examined.

RESULTS

Renal IR injury significantly reduced the Nrf-2 expression, superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT) enzymes' activities and TAC. Moreover, Malondialdehyde (MDA) level in kidney and heart tissues, plasma creatine kinase-MB (CK-MB), and lactate dehydrogenase (LDH) activity were increased, and ECG parameters were significantly distributed; however, NAR, TMZ, or their combination improved these changes, in comparison with the renal IR injury in rats.

CONCLUSION

NAR, TMZ, or their combination could attenuate the Nrf-2 expression in the kidney tissue, following the renal IR injury through inhibition of lipid peroxidase, and enhancement of antioxidant activity.

Trimetazidine ameliorates sunitinib-induced cardiotoxicity in mice via the AMPK/mTOR/autophagy pathway

Context: Sunitinib (SU) is a multi-targeted tyrosine kinase inhibitor anticancer agent whose clinical use is often limited by cardiovascular complications. Trimetazidine (TMZ) is an anti-angina agent that has been demonstrated cardioprotective effects in numerous cardiovascular conditions, but its potential effects in SU-induced cardiotoxicity have not been investigated. Objective: This study investigates the effect of TMZ in sunitinib-induced cardiotoxicity in vivo and in vitro and molecular mechanisms. Materials and methods: Male 129S1/SvImJ mice were treated with vehicle, SU (40 mg/kg/d) or SU and TMZ (20 mg/kg/d) via oral gavage for 28 days, and cardiovascular functions and cardiac protein expressions were examined. H9c2 cardiomyocytes were treated with vehicle, SU (2-10 μM) or SU and TMZ (40-120 μM) for 48 h, and cell viability, apoptosis, autophagy, and protein expression was tested. Results: SU induces hypertension (systolic blood pressure [SBP] + 28.33 ± 5.00 mmHg) and left ventricular dysfunction (left ventricular ejection fraction [LVEF] - 11.16 ± 2.53%) in mice. In H9c2 cardiomyocytes, SU reduces cell viability (IC₅₀ 4.07 μM) and inhibits the AMPK/mTOR/autophagy pathway (p < 0.05). TMZ co-administration with SU reverses SU-induced cardiotoxicity in mice (SBP - 23.75 ± 4.69 mmHg, LVEF + 10.95 ± 3.317%), alleviates cell viability loss in H9c2 cardiomyocytes (p < 0.01) and activates the AMPK/mTOR/autophagy pathway in vivo (p < 0.001) and in vitro (p < 0.05). Discussion and conclusions: Our results suggest TMZ as a potential cardioprotective approach for cardiovascular complications during SU regimen, and potentially for cardiotoxicity of other anticancer chemotherapies associated with cardiomyocyte autophagic pathways.

Effects of trimetazidine on nerve regeneration in a rat sciatic nerve injury model

AIM

The aim of this study was to evaluate the efficacy of trimetazidine(TMZ) after end-to-end repair in a peripheral nerve injury model.

METHOD

We performed end-to-end primary repair of sciatic nerves in rats and showed TMZ's regenerative effect. For this objective 30 male Sprague Dawley albino rats were used. Surgery+water group, rats were assigned to a placebo group and were given water by oral gavage. Surgery+TMZ group, rats were given trimetazidine by oral gavage. All medications were given for 12 weeks. Motor function test was performed. Afterwards, electromyography (EMG) recording was done. Finally, blood samples were taken, the animals were euthanized andsciatic nerve was removed.

RESULTS

The amplitudes of compound muscle action potential (CMAP) increased significantly in the Surgery+TMZ group when compared with the group that have been given Surgery+Water. Nerve growth factor (NGF) immunoexpression in the Schwann cell was significantly increased in the Surgery+TMZ group compared with the Surgery+Water group. Moreover, fibrosis score was reduced in the Surgery+TMZ group compared to the Surgery+Water group.CONCLUSİONS: In conclusion, we demonstrated the superiority of TMZ on nerve healing in our experimental study which was evaluated with comparative groups (Tab. 3, Fig. 2, Ref. 31).

[Effect of trimetazidine on cardiac function and exercise tolerance in hypertension patients with diabetic]

OBJECTIVE

To determine the effect of trimetazidine on cardiac function and exercise tolerance in primary hypertension patients with type 2 diabetic.

METHODS

In this randomized, double-blind, placebo-controlled prospective study, 60 primary hypertensive patients with diabetic were equally assigned into two groups, patients received trimetazidine (20 mg, 3 times a day) or placebo for 1 year. Echocardiography, cardiopulmonary exercise testing were performed; and the plasma N terminal pro B type natriuretic peptide (NT-ProBNP), hr-CRP, TNF-α, angiotensin Ⅱ and endothelin concentration were determined before and after treatment.

RESULTS

In trimetazidine group, the left ventricular mass index, the mitral flow velocity E wave to A wave ratio (E/A), the peak early diastolic velocity (V_E) to late diastolic velocity (V_A) ratio (V_E/V_A) and the peak systolic velocity (Vs) were significantly improved, the plasma NT-ProBNP level was significantly decreased, and the exercise time, metabolic equivalent, maximal oxygen uptake and anaerobic threshold were significantly increased (all P<0.05); plasma concentration of hr-CRP, TNF-α, angiotensin Ⅱ and endothelin were significantly reduced after trimetazidine treatment, compared with baseline (all P<0.05) and with placebo (all P<0.05). There were no significant differences in any of above parameters after treatment in placebo group (all P>0.05). No severe adverse reaction was observed in both groups.

CONCLUSIONS

For patients with both hypertension and diabetes, trimetazidine can improve cardiac function and increase exercise tolerance.

Trimetazidine attenuates high-altitude fatigue and cardiorespiratory fitness impairment: A randomized double-blinded placebo-controlled clinical trial

Trimetazidine (TMZ) has been shown to optimize myocardial energy metabolism and is a common anti-ischemic agent. Our trial (ChiCTR-TRC-13003298) aimed to explore whether TMZ has any preventive effect on high-altitude fatigue (HAF), cardiac function and cardiorespiratory fitness upon acute high-altitude exposure and how it works on HAF. Thirty-nine healthy young subjects were enrolled in a randomized double-blinded placebo-controlled trial and were randomized to take oral TMZ (n = 20) or placebo (n = 19), 20 mg tid, 14 days prior to departure until the end of study. The 2018 Lake Louise Score questionnaire, echocardiography, assessments of physical working capacity, circulating markers of myocardial energy metabolism and fatigue were performed both before departure and arrival at highland. At follow-up, TMZ significantly reduced the incidence of HAF (p = 0.038), reversed cardiorespiratory fitness impairment, decreased left ventricular end-systolic volume (LVESV, p = 0.032) and enhanced left ventricular ejection fraction (LVEF, p = 0.015) at highland. Relative to the placebo group, the TMZ group had significantly lower LDH (p = 0.025) and lactate levels before (p < 0.001) and after (p = 0.012) physical exercise after acute high-altitude exposure. Additionally, improved left ventricular systolic function might have contributed to ameliorating HAF during TMZ treatment (LVEF, OR = 0.859, 95% CI = 0.741-0.996, p = 0.044). In conclusion, our results demonstrated that TMZ could prevent HAF, cardiorespiratory fitness impairment and improves left ventricular systolic function during acute high-altitude exposure. This trial provides new insights into the effect of TMZ and novel evidence against HAF and cardiorespiratory fitness impairment at highland.

Trimetazidine and parkinsonism: A prospective study

BACKGROUND

Although trimetazidine may induce parkinsonian symptoms in some patients, no systematic characterization has been reported on parkinsonism occurring during trimetazidine treatment since the first case reports.

OBJECTIVE

To systematically investigate parkinsonism occurring during trimetazidine use.

METHODS

Thirty-three consecutive patients on trimetazidine treatment with previously unrecognized parkinsonian symptoms were enrolled. Detailed neurological and neuropsychological examinations were performed at baseline and 1 and 12 months after trimetazidine withdrawal. In cases with persisting parkinsonian symptoms and suspected de novo Parkinson's disease, antiparkinsonian treatment was initiated. Twenty of the 33 patients underwent DaTSCAN imaging.

RESULTS

After trimetazidine withdrawal, parkinsonism was completely resolved in 11 cases. The comparison of baseline data of patients with reversible and persisting parkinsonism showed that trimetazidine-induced reversible parkinsonism was mainly characterized by akinesia, rigidity, postural instability and gait disturbances (PIGD; PIGD scores: 5.3 ± 3.8 vs. 2.0 ± 1.6 points, p = 0.006) rather than tremors (tremor scores: 1.5 ± 2.2 vs. 7.7 ± 4.6 points, p = 0.000). Trimetazidine-induced reversible parkinsonism was also more symmetrical (asymmetry index: 3.1 ± 3.6 vs. 40.1 ± 22.2, p = 0.000) and milder in severity (MDS-UPDRS Part III. scores: 10.5 ± 19. vs. 30.5 ± 11.3, p = 0.040) than nonreversible parkinsonism. DaTSCAN images were normal in all trimetazidine-induced reversible parkinsonism patients, while these images were abnormal in every patient with nonreversible parkinsonism. In cases of nonreversible parkinsonism, preexisting, incipient Parkinson's disease was suspected by clinical appearance and a good response to antiparkinsonian medication.

CONCLUSIONS

Mild and symmetrical appearance of parkinsonism with normal DaTSCAN results can indicate drug-induced parkinsonism. Trimetazidine discontinuation generally results in permanent remission in such cases.

Medical and social issues of cardiovascular diseases and their solution based on the experimental study of myocardial fibrosis

OBJECTIVE

Introduction: The prevalence and incidence of cardiovascular diseases have been attracting considerable attention in recent decades. This is partly due to the fact that myocardial fibrosis is the major consequence of the most nosological units of cardiovascular diseases. We believe that early pathogenic therapy of myocardial fibrosis should be taken into consideration as a solution to this issue. The change of the connective tissue metabolism in myocardium is the central chain in pathogenesis of diffuse ischemic necrotic cardiosclerosis (DINC) occurs after repeated epinephrine injury of myocardial tissues. The aim: The present study establishes that use of metabolic therapy by trimetazidine (TM) has a protective effect on myocardium repeatedly damaged by epinephrine in hight concentration during the development of DINC in rats with different resistance to hypoxia.

PATIENTS AND METHODS

Materials and methods: Using the method of hypobaric hypoxia, male albino rats were divided into three groups due to their different resistance to hypoxia. Each group was divided into four equal subgroups: control group, DINC group (2 times repeated injections of epinephrine hydrotartrate (0,5 mg/kg body weight) and calcium gluconate (5 mg/ kg body weight), control group introdused with trimetazidine dihydrochloride (10 mg/kg body weight), DINC treated with TM group (2 times repeated injections of epinephrine hydrotartrate (0,5 mg/kg body weight) and calcium gluconate (5 mg/kg body weight) group introduced with TM (10 mg/kg body weight) for all period of observation. The concentration of protein-bound oxyproline in homogenate of myocardium was determined at 7, 14 and 30 days after the modelling pathology and the histological examination of Masson trichrome staining of myocardium was performed.

RESULTS

Results: Experimental modeling of DINC increased the concentration of protein-bound oxyproline in homogenate of myocardium at 7, 14 and 30 days after the modelling pathology, as well as accompanied by metabolic imbalances in diffuse connective tissue elements, which are rich in collagens. Experimental modeling of DINC+TM increased the concentration of protein-bound oxyproline in blood serum significantly less intensive.

CONCLUSION

Conclusions: The intensity of metabolic imbalances in diffuse connective tissue elements of myocardium is the highest in the low resistant animals to hypoxia. Those results are confirmed by histological examination of the myocardium of rats with different resistance to hypoxia. Fibrotic regions in myocardium are rich in collagens. It has been revealed that the most pronounced therapeutic effect of TM is observed in animals with low resistance to hypoxia, slightly less - in animals with medium resistance to hypoxia, and the lowest - in animals with high resistance to hypoxia.

Trimetazidine Protects Against Atherosclerosis by Changing Energy Charge and Oxidative Stress

BACKGROUND This study investigated the effect and the possible mechanism of trimetazidine in atherosclerosis. MATERIAL AND METHODS We established an atherosclerotic rat model by high-fat diet and vitamin D injection. Rats were separated into 3 different groups: control, atherosclerosis, and trimetazidine (n=10). The aortic artery was isolated and its morphological features were examined by hematoxylin and eosin (HE) staining. Serum low-density lipoprotein cholesterol (LDL-c), total cholesterol (TC), and triglycerides (TG) were analyzed using an automatic biochemical analyzer. Human aortic smooth muscle cells (HASMCs) were cultured and divided into 5 groups: no treatment, H₂O₂ treatment only, trimetazidine preincubation before H₂O₂ treatment, oxidized low-density lipoprotein (oxLDL) treatment only, and trimetazidine preincubation before oxLDL treatment. HASMCs proliferation was tested using the Cell Counting Kit-8. Reactive oxygen species (ROS) and malondialdehyde (MDA) levels, superoxide dismutase (SOD) activity of the aortic artery, and HASMCs were measured using commercially available kits. RESULTS HE staining assay showed that trimetazidine suppressed the progression of atherosclerosis and reduced foam cell formation in the aortic artery without affecting serum lipid levels. HASMCs proliferation assay revealed that trimetazidine alleviated the inhibitory effect of H₂O₂ on HASMCs proliferation and inhibited oxLDL-induced proliferation of HASMCs. Moreover, trimetazidine ameliorated ROS up-regulation elicited by H₂O₂ or oxLDL in HASMCs. Additionally, trimetazidine restored SOD activity and reduced MDA content of HASMCs. CONCLUSIONS Trimetazidine suppressed the progression of atherosclerosis by enhancing energy value, decreasing ROS level of aortic artery, modulating HASMCs proliferation, and reducing oxidative stress in HASMCs.

[Trimetazidine reduces cholesterol content of foam cells by up-regulating autophagy and macrophage extracellular traps, and inhibiting inflammasome]

Objective To explore the effects of trimetazidine (TMZ) on the foam cell formation and its underlying mechanism in oxidized low-density lipoprotein (ox-LDL)-induced macrophages. Methods RAW264.7 cells were stimulated with ox-LDL to establish a foam cell model derived from macrophages. In the experiment, the foam cells were divided into control group (medium), model group (ox-LDL 60 μg/mL), chloroquine (CQ) group (ox-LDL 60 μg/mL combined with CQ 10 mmol/L) and TMZ group (ox-LDL 60 μg/mL combined with TMZ 80 μmol/L, CQ 10 mmol/L). The formation of foam cells was measured by oil red O staining. The levels of total cholesterol (TC) and free cholesterol (FC) in the foam cells were detected using ELISA. Autophagy was observed using MDC staining. Picogreen staining and quantitative fluorescence were performed to detect the formation of macrophage extracellular traps (MET). Then, the mRNA expression of LC3B, P62, inflammasome (NLRP3, ASC, caspase-1) and cholesterol efflux-related genes (ABCA1, ABCG1) were examined by real-time quantitative PCR. Results Compared with the model group, the expression of LC3B mRNA increased significantly, and P62 expression decreased in TMZ combined with CQ group. Meanwhile, the levels of TC, FC, CE/TC, and the expression of NLRP3, ASC, caspase-1 in TMZ combined with CQ group were reduced obviously. Furthermore, the formation of MET in TMZ combined with CQ group was promoted. However, the CQ group showed the opposite results. Conclusion Trimetazidine promotes cholesterol efflux in foam cells via activating autophagy and increasing the formation of MET, as well as inhibiting NLRP3 inflammasome.

Trimetazidine ameliorates myocardial ischemia-reperfusion injury

Aim of this study was to investigate the effects of trimetazidine attenuating the myocardial ischemia-reperfusion injury to myocardium in rats and the underlying mechanisms. A model of myocardial ischemia reperfusion was established via ligating the left anterior descending coronary artery in 30 rats, and then they were randomly assigned to model group (n=10), low dose group (n=10) and high dose group (n=10). Moreover, additional 10 rats were collected and allocated to sham operation group, which was served as control group. Then, rats in the low dose group and high dose group were given trimetazidine with the dose of 10mg/kg and 30mg/kg respectively by intragastric administration, while rats in the control group and model group were given the equivalent volume saline. The dose was given once a day for consecutive 4 weeks in all rats. Echocardiography was applied to evaluate cardiac function, including left ventricular end-systolic dimension (LVESD), left ventricular end diastolic dimension (LVEDD) and left ventricular ejection fraction (LVEF). Next, myocardial tissue was collected, and Bax and Bcl-2 mRNA and the protein levels in the four groups were detected by RT-PCR and Western blot respectively. The level of malonaldehyde (MDA) and super oxide dismutase (SOD) activity in rat myocaridum in each group were detected by colorimetric methods, while the variables of apoptosis were measured by TUNEL methods. In comparison with the control group, LVEDD, LVEDS of rats increased significantly, LVEF decreased obviously, as well as Bax level, MDA level and the apoptotic variables in myocardial tissue increased (P<0.05), but Bcl-2 level and SOD activity decreased significantly in low dose, high dose and model group (P<0.05). Compared with model group, LVEDD, LVEDS of rats decreased obviously, LVEF increased significantly, as well as Bax level, MDA level and the apoptotic variables in myocardial tissue decreased (P<0.05), but Bcl-2 level and SOD activity increased significantly in low dose group, high dose group (P<0.05). The regulatory role of trimetazidine on above indicators of rats was in a dose-dependent manner. Trimetazidine can ameliorate rat myocardium following ischemia-reperfusion injury by effectively attenuating the injury from myocardial cell apoptosis; meanwhile, it can resist cell apoptosis through regulating Bax and bcl-2 expression, which exhibits guiding significance for the treatment of myocardial ischemia and reperfusion.

Trimetazidine restores the positive adaptation to exercise training by mitigating statin-induced skeletal muscle injury

BACKGROUND

Exercise rehabilitation is demonstrated to improve the prognosis of patients with coronary heart disease (CHD). Statins, as the key medicine to lower cholesterol in CHD, result in skeletal muscle injury and impair exercise training adaptation. Energy metabolism dysfunction is identified as the potential mechanism underlying statin-induced skeletal muscle injury. In this study, we investigated the effects of the metabolic modulator trimetazidine on skeletal muscle energy metabolism and statin-associated exercise intolerance.

METHODS

High-fat fed apolipoprotein E knockout (ApoE-/- ) mice were given aerobic exercise and administrated simvastatin, trimetazidine, or simvastatin plus trimetazidine by gavage. Exercise capacity was evaluated at the end of the treatment by hanging grid test, forelimb grip strength, and running tolerance test. Plasma glucose, lipid, and creatine kinase concentrations were measured at the end of the treatment. After sacrifice, gastrocnemii were stored for assessment of muscle morphology and fibre type. Energy metabolism was estimated by plasma lactic acid concentration, ragged red fibres, and glycogen stores. Activities of mitochondrial complex III, citrate synthase activity, and membrane potential were measured to assess mitochondrial function. Oxidative stress was also evaluated by superoxide in mitochondria, superoxide dismutase activity, and glutathione redox state.

RESULTS

In high-fat fed ApoE-/- mice, exercise training had no effect on lipid concentrations. Lower lipid concentrations with increased creatine kinase were observed with additional simvastatin treatment. Exercise capacity increased significantly in response to exercise training alone but was blunted by the addition of simvastatin. Similarly, cross-sectional area of muscle fibres and the proportion of slow-twitch fibres increased in the exercise group but decreased in the simvastatin plus exercise group. Additionally, simvastatin increased centronucleated fibres and induced energy metabolism dysfunction by inhibiting complex III activity and thus promoted oxidative stress in gastrocnemius. We demonstrated that trimetazidine could reverse simvastatin-induced exercise intolerance and muscle damages. We also found the ability of trimetazidine in restoration of muscle fibre hypertrophy and facilitating fast-to-slow type shift. The energy metabolism dysfunction and oxidative stress in gastrocnemii were rescued by trimetazidine.

CONCLUSIONS

Trimetazidine alleviated statin-related skeletal muscle injury by restoration of oxidative phenotype and increasing fibre cross-sectional areas in response to exercise training. Correspondingly, the exercise training adaptation were improved in high-fat fed ApoE-/- mice. Moreover, trimetazidine is able to exert its positive effects without affecting the beneficial lipid-lowering properties of the statins. Thus, trimetazidine could be prescribed to remedy the undesirable statins-induced exercise intolerance during cardiac rehabilitation in patients with CHD.

[Effects of trimetazidine, a myocardial metabolism agent, on regulating 5-hydroxytrytamine system of rats with myocardial infarction and/or depression]

Objective: 5-Hydroxytrytamine (5-HT) system was reported to be associated with myocardial infarction (MI) and depression. The aim of the present study was to study the effect of trimetazidine on 5-HT in MI and/or depression rats. Methods: Ninety rats were divided into three groups: trimetazidine, sertraline and saline groups (n=30 in each group), and pretreated with trimetazidine, sertarline, or saline, respectively, by gavage once a day for 4 weeks. Thereafter, each group was further divided into three subgroups: MI subgroup, depression subgroup, and MI+ depression subgroup. Serum 5-HT, platelet 5-HT, 5-HT(2A) receptor (5-HT(2A)R), and serotonin transporter (SERT) were detected by enzyme linked immunosorbent assay. Results: Similar to sertarline, comparing to saline, trimetazidine treatment increased serum 5-HT [(221±23) pg/ml vs. (176±11) pg/ml; (395±31) pg/ml vs. (195±5) pg/ml; (348±28) pg/ml vs. (183±10) pg/ml], platelet 5-HT [(305±22) pg/ml vs. (130±27) pg/ml; (252±18) pg/ml vs. (175±5) pg/ml; (241±26) pg/ml vs. (181±11) pg/ml], and platelet 5-HT(2A)R levels [(247±13) pg/ml vs. (197±12) pg/ml; (320±13) pg/ml vs. (193±18)pg/ml; (334±17) pg/ml vs. (206±15) pg/ml]), and lowered platelet SERT levels [(248±11) pg/ml vs. (323±36) pg/ml; (188±7) pg/ml vs. (278±20) pg/ml; (170±23) pg/ml vs. (282±22) pg/ml] in MI, depression and MI+ depression subgroups, respectively (all P< 0.05). When compared the effect of trimetazidine and sertarline treatment, serum 5-HT and platelet 5-HT(2A)R in MI group were significantly lower in trimetazidine than in sertraline group (P<0.05), while serum 5-HT and platelet 5-HT, 5-HT(2A)R in depression group rats were significantly higher in trimetazidine than in sertraline group (P<0.05).Interestingly, platelet 5-HT(2A)R in MI+ depression rats was much higher in trimetazidine than in sertraline group (P<0.05). Conclusions: Trimetazidine, a kind of myocardial metabolism agent, could play a role on the regulation of 5-HT, 5-HT(2A)R, and SERT levels in rats with MI and/or depression.

Trimetazidine therapy for diabetic mouse hearts subjected to ex vivo acute heart failure

Acute heart failure (AHF) is the most common primary diagnosis for hospitalized heart diseases in Africa. As increased fatty acid β-oxidation (FAO) during heart failure triggers detrimental effects on the myocardium, we hypothesized that trimetazidine (TMZ) (partial FAO inhibitor) offers cardioprotection under normal and obese-related diabetic conditions. Hearts were isolated from 12-14-week-old obese male and female diabetic (db/db) mice versus lean non-diabetic littermates (db/+) controls. The Langendorff retrograde isolated heart perfusion system was employed to establish an ex vivo AHF model: a) Stabilization phase—Krebs Henseleit buffer (10 mM glucose) at 100 mmHg (25 min); b) Critical Acute Heart Failure (CAHF) phase–(1.2 mM palmitic acid, 2.5 mM glucose) at 20 mmHg (25 min); and c) Recovery Acute Heart Failure phase (RAHF)–(1.2 mM palmitic acid, 10 mM glucose) at 100 mmHg (25 min). Treated groups received 5 μM TMZ in the perfusate during either the CAHF or RAHF stage for the full duration of each respective phase. Both lean and obese males benefited from TMZ treatment administered during the RAHF phase. Sex differences were observed only in lean groups where the phases of the estrous cycle influenced therapy; only the lean follicular female group responded to TMZ treatment during the CAHF phase. Lean luteal females rather displayed an inherent cardioprotection (without treatments) that was lost with obesity. However, TMZ treatment initiated during RAHF was beneficial for obese luteal females. TMZ treatment triggered significant recovery for male and obese female hearts when administered during RAHF. There were no differences between lean and obese male hearts, while lean females displayed a functional recovery advantage over lean males. Thus TMZ emerges as a worthy therapeutic target to consider for AHF treatment in normal and obese-diabetic individuals (for both sexes), but only when administered during the recovery phase and not during the very acute stages.

GSK3β and VDAC Involvement in ER Stress and Apoptosis Modulation during Orthotopic Liver Transplantation

We investigated the involvement of glycogen synthase kinase-3β (GSK3β) and the voltage-dependent anion channel (VDAC) in livers subjected to cold ischemia-reperfusion injury (I/R) associated with orthotopic liver transplantation (OLT). Rat livers were preserved in University of Wisconsin (UW) and Institute Georges Lopez (IGL-1) solution, the latter enriched or not with trimetazidine, and then subjected to OLT. Transaminase (ALT) and HMGB1 protein levels, glutamate dehydrogenase (GLDH), and oxidative stress (MDA) were measured. The AKT protein kinase and its direct substrates, GSK3β and VDAC, as well as caspases 3, 9, and cytochrome C and reticulum endoplasmic stress-related proteins (GRP78, pPERK, ATF4, and CHOP), were determined by Western blot. IGL-1+TMZ significantly reduced liver injury. We also observed a significant phosphorylation of AKT, which in turn induced the phosphorylation and inhibition of GSK3β. In addition, TMZ protected the mitochondria since, in comparison with IGL-1 alone, we found reductions in VDAC phosphorylation, apoptosis, and GLDH release. All these results were correlated with decreased ER stress. Addition of TMZ to IGL-1 solution increased the tolerance of the liver graft to I/R injury through inhibition of GSK3β and VDAC, contributing to ER stress reduction and cell death prevention.

[The Mechanisms of Trimetazidine Alleviating the Oxidative Stress in Adipose-derived Mesenchymal Stem Cells]

OBJECTIVES

To investigate the effects of trimetazidine (TMZ) on the oxidative stress injury in adipose-derived mesenchymal stem cells (ADSCs).

METHODS

ADSCs derived from adipose tissue of SD rats were characterized by flow cytometry and multiline age differentiation. ADSCs apoptosis was induced by H2O2 in vitro , Dirrerent concentration of TMZ (250 μmol/L, 500 μmol/L) was used to protect ADSCs from apoptosis. The morphological features of apoptotic ADSCs were analyzed by Hoechst 33342, mitochondrial potential and structure was analyzed by JC-1 staining and electron microscope, respectively. The apoptotic proteins were detected by Western blot. The effect of TMZ on antioxidant capacity of ADSCs was evaluated by detecting reactive oxygen species (ROS), superoxide dismutase (SOD), glutathione (GSH) and malondialdehyde (MDA).

RESULTS

The isolated ADSCs expressed high levels of CD29 and CD90, low levels of CD34 and CD45 and no expression of CD31. ADSCs could be induced to adipocyte and osteoplastic cells. After being treated by H2O2, ADSCs displayed apoptosis characteristics with increased number of apoptotic cells, decreased mitochondrial transmembrane potential and damaged mitochondria. The expressions of apoptotic proteins, including Bax, Bad, and Caspase3, were dramatically increased compared to the controls; however, the anti-apoptotic protein Bcl2 was decreased. At the meantime, the contents of ROS and MDA were elevated, but the concentrations of SOD and GSH were reduced. The treatment of TMZ could partly reverse above negative impacts to ADSCs.

CONCLUSION

TMZ could improve the survival rate of ADSCs by enhancing anti-oxidant defense systems to remove excessive ROS and regulating the expression of protective protein.

[Impact of trimetazidine pre-treatment on 5-hydroxytryptamine and serotonin transporter in rats with experimental myocardial infarction and depression]

Objective: To explore the effect of trimetazidine pre-treatments on serum 5-hydroxytryptamine (5-HT) and serotonin transporter (SERT), platelet 5-HT and SERT in the Sprague Dawley rats with myocardial infarction(MI), depression, and myocardial infarction co-exist with depression (MI+ depression) and in sham operated rats. Methods: Eighty rats were divided into treatment group and placebo (saline) group by the random number table method (n=40 each group). After 4 weeks' treatment with trimetazidine, or saline, these rats were assigned to respective sham subgroup, depression subgroup, MI subgroup, MI + depression subgroup (n=10 each subgroup). All rats were sacrificed 3 days later. 5-HT in serum and platelet, and SERT in serum and platelet of the rats were tested by enzyme linked immunosorbent assay (ELISA). Data were analyzed by SPSS 17.0. Results: In saline group, serum and platelet 5-HT levels were significantly lower in MI, depression and MI+ depression subgroup compared to sham subgroup (all P<0.01). In trimetazidine pre-treatment group, serum and platelet 5-HT levels were significantly higher in the depression subgroup, MI subgroup, MI + depression subgroup than respective subgroups of saline pretreated rats (all P<0.01). In saline group, SERT in serum and platelet were higher in MI, depression, MI+ depression subgroup than the sham subgroup and statistical significance was found between MI+ depression subgroup and sham subgroups. Serum SERT level was significantly lower in the treatment group compared to saline group for sham rats (P<0.01). In treatment group, serum SERT level was higher in MI, depression and MI+ depression subgroups compared to respective subgroup treated with saline while the statistical significance was found in depression subgroup between trimetazidine pre-treatment and saline control groups. Platelet SERT was higher in MI, depression and MI+ depression subgroups compared to sham subgroup post saline treatment. Platelet SERT was significantly lower in MI, depression and MI+ depression subgroups post trimetazidine pre-treatment than in respective subgroups post saline treatment (all P<0.01). Conclusions: Our study results indicate that trimetazidine pretreatment could increase the levels of 5-HT and SERT in serum and 5-HT in platelet, and decrease the level of SERT in platelet in the rat MI and depression model.

Evaluation of the Protective Effect of NMDA/Non-NMDA Receptor Antagonists Against Ethambutol Induced Retinal Toxicity Using ERG in Wistar Rats

To study the protective effect of NMDA and non-NMDA receptor antagonists against ethambutol (EMB) induced retinal toxicity in Wistar rats using flash electroretinogram (ERG). Rats were randomized into four groups: Group-1 received vehicle. Group-2 received oral EMB (200 mg/kg/day). Group-3 and 4 were fed with oral EMB along with memantine (MEM) (1 mg/kg, ip) and trimetazidine (TMZ) (3mg/kg, ip) respectively. All treatments were continued up to 28 days. ERG was recorded at 0 and 21st day using green and white lights. Ethambutol and 2, 2’ ethylene diimino dibutyric acid (EDBA) levels were quantified in rat body fluids and tissues using LC-MS/MS. A higher rate of rat mortality was observed between 21st and 28th day, 21st day considered for ERG recording among groups. Ethambutol did not cause any significant change in ‘a’-wave amplitude of rat ERG but caused a predictable decrease in ‘b’-wave amplitude of the rat ERG on the 21st day. Memantine treatment showed a significant (P=0.029) protection against the fall of ‘b’-wave amplitude on 21st day. Interestingly, we found that plasma levels of EMB in memantine treated rats were significantly reduced when compared to the positive control group. Memantine reversed the effects of EMB on ‘b’-wave of rat ERG suggests its protective role. We suggest MEM may be considered as a possible preventive treatment modality for EMB induced vision toxicity warranting further clinical investigations.

Metabolic Modulators for Chronic Cardiac Ischemia

Many patients with ischemic heart disease continue to experience anginal symptoms despite revascularization and treatment with antianginal medications. The effectiveness of current anti-ischemic medications is limited by their hemodynamic side effects, such as hypotension and bradycardia, which result in compromised organ perfusion. In this article, we review five novel agents (ranolazine, trimetazidine, L-carnitine, ribose, and dichloroacetate) under investigation for treatment of ischemic heart disease that work by enhancing the efficiency of the myocardium, rather than decreasing its work. This new paradigm promises to eliminate these side effects.

Effects of Trimetazidine on Lipid Peroxidation, Antioxidant Enzyme Activities and Plasma Brain Natriuretic Peptide Levels in Patients with Chronic Cor Pulmonale

An oxidant/antioxidant imbalance in favour of oxidants appears to occur in chronic cor pulmonale (CCP). Oxidative stress could also be a critical event in the pathogenesis of this condition. Trimetazidine (TMZ) has antioxidant properties and may affect the utilization of oxygen radicals. We investigated the effect of TMZ (20 mg three times daily, orally) on activities of erythrocyte malondialdehyde (MDA) and catalase (eCAT), erythrocyte and plasma glutathione peroxidase (GSH-Px) and plasma superoxide dismutase (pSOD) in CCP patients. We also assessed changes in plasma levels of brain natriuretic peptide (BNP) with TMZ therapy.

Sixty CCP patients with significantly higher MDA and markedly lower pSOD, eCAT and GSH-Px (erythrocyte) activities than 24 healthy controls were randomly allocated to receive routine treatment or routine treatment plus TMZ. After 3 months' therapy, greater pSOD, eCAT and GSH-Px (erythrocyte and plasma) activities and lower MDA activity were found with TMZ treatment compared with routine treatment. Plasma BNP levels were significantly lower in TMZ-treated patients and higher in the routine treatment group than in the control group. TMZ improved antioxidant levels, decreased oxidative stress and decreased plasma BNP levels in CCP patients.

Role of Trimetazidine in Ischemic Preconditioning in Patients With Symptomatic Coronary Artery Disease

Ischemic preconditioning (IP) is a powerful cardioprotective cellular mechanism that has been related to the "warm-up phenomenon" or "walk-through" angina, and has been documented through the use of sequential exercise tests (ETs). It is known that several drugs, for example, cromokalim, pinacidil, adenosine, and nicorandil, can interfere with the cellular pathways of IP. The purpose of this article is to report the effect of the anti-ischemic agent trimetazidine (TMZ) on IP in symptomatic coronary artery disease (CAD) patients.We conducted a prospective study evaluating IP by the analysis of ischemic parameters in 2 sequential ETs. In phase I, without TMZ, patients underwent ET1 and ET2 with a 30-minute interval between them. In phase II, after 1 week of TMZ 35 mg twice daily, all patients underwent 2 consecutive ETs (ET3 and ET4). IP was considered present when the time to 1.0-mm segment ST on electrocardiogram deviation (T-1.0 mm) and rate pressure product (RPP) were greater in the second of 2 tests. The improvement in T-1.0 mm and RPP were compared in the 2 phases: without TMZ and after 1-week TMZ to assess the action of such drug in myocardial protective mechanisms. ETs were analyzed by 2 independent cardiologists.From 135 CAD patients screened, 96 met inclusion criteria and 62 completed the study protocol. Forty patients manifested IP by demonstrating an improvement in T-1.0 mm in ET2 compared with ET1, without the use of any drugs (phase I). In phase II, after 1-week TMZ, 26 patients (65%) did not show any incremental result in ischemic parameters in ET4 compared with ET3. Furthermore, of these patients, 8 (20%) had IP blockage.In this study, TMZ did not add any benefit to IP in patients with stable symptomatic CAD.

Appreciation of trimetazidine treatment in experimental sepsis rat model

INTRODUCTION

Our aim was to determine the efficacy of trimetazidine on experimental sepsis rat model.

MATERIAL AND METHODS

Sixty rats were randomized into three groups. In Group 1, sepsis was induced. In Group 2, sepsis was induced and as a therapeutic agent trimetazidine was given. In Group 3, rats were sham operated. Serum interleukin-1 beta (IL-1ß), tumor necrosis factor alfa (TNF-α), superoxide dismutase (SOD), glutathion peroxidase (GSH-Px) and malondialdehyde (MDA) levels were determined in all groups.

RESULTS

In Group 2, serum GSH-Px and SOD levels were statistically significantly higher than in Group 1 (p< 0.05) and serum MDA levels were statistically significantly lower than in group 1 (p < 0.05). Trimetazidine also significantly decreased the levels of IL-1ß and TNF-a which are the proinflammatory cytokines (p < 0.05).

CONCLUSION

Trimetazidine treatment significantly improved inflammation, oxidative stress and membrane destruction in LPS-induced sepsis. As the proinflammatory cytokines are supposed to play a primary role in the pathogenesis of sepsis, we assumed that the trimetazidine treatment would give new insights into the treatment of sepsis (Tab. 1, Fig. 5, Ref. 29).

Trimetazidine protects against hypoxia-reperfusion-induced cardiomyocyte apoptosis by increasing microRNA-21 expression

Myocardial tissue injury caused by ischemia and hypoxia is a major cause of fatal diseases, including coronary atherosclerosis resulting from myocardial infarction and stroke. Trimetazidine (TMZ), as an anti-ischemic and antioxidant agent, has been demonstrated to preventing ischemia/reperfusion-induced cardiomyocyte apoptosis. However, the anti-apoptosis mechanism of TMZ has not been fully elucidated. The present study demonstrated that miR-21 involved trimetazidine-induced anti-apoptosis during H/R injury in H9C2 cell. In this study, TMZ increased miR-21 expression which further upregulated the Akt signaling activity via suppressing the expression of phosphatase and tensin homolog (PTEN) in H/R H9C2 cell. The increased activity of Akt signaling decreased the ratio of Bax/Bcl-2 and the expression of caspase-3 and inhibited H/R induced apoptosis. In conclusion, this study revealed the mechanism that TMZ up-regulated miR-21 expression, then miR-21 targeted PTEN increasing the PI3K pathway and finally the activation of this pathway counteracted the apoptotic effect of hypoxia/reperfusion.