Trimetazidine revisited: a comprehensive review of the pharmacological effects and analytical techniques for the determination of trimetazidine

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.

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.

Neuroprotective effects of combined trimetazidine and progesterone on cerebral reperfusion injury

Cerebral ischemia-reperfusion injury induces multi-dimensional damage to neuronal cells through exacerbation of critical protective mechanisms.

Targeting more than one mechanism simultaneously namely, inflammatory responses and metabolic energy homeostasis could provide additional benefits to restrict or manage cerebral injury. Being proven neuroprotective agents both, progesterone (PG) and trimetazidine (TMZ) has the potential to add on the individual therapeutic outcomes.

We hypothesized the simultaneous administration of PG and TMZ could complement each other to synergize, or at least enhance neuroprotection in reperfusion injury. We investigated the combination of PG and TMZ on middle cerebral artery occlusion (MCAO) induced cerebral reperfusion injury in rats. Molecular docking on targets of energy homeostasis and apoptosis assessed the initial viability of PG and TMZ for neuroprotection. Animal experimentation with MCA induced ischemia-reperfusion (I/R) injury in rats was performed on five randomized groups.

Sham operated control group received vehicle (saline) while the other four I-R groups were pre-treated with vehicle (saline), PG (8 ​mg/kg), TMZ treated (25 ​mg/kg), and PG ​+ ​TMZ (8 and 25 ​mg/kg) for 7 days by intraperitoneal route. Neurological deficit, infarct volume, and oxidative stress were evaluated to assess the extent of injury in rats. Inflammatory reactivity and apoptotic activity were determined with alterations in myeloperoxidase (MPO) activity, blood-brain barrier (BBB) permeability, and DNA fragments. Reperfusion injury inflicted cerebral infarct, neurological deficit, and shattered BBB integrity.

The combination treatment of PG and TMZ restricted cellular damage indicated by significant (p ​< ​0.05) decrease in infarct volume and improvement in free radical scavenging ability (SOD activity and GSH level). MPO activity and LPO decreased which contributed in improved BBB integrity in treated rats. We speculate that inhibition of inflammatory and optimum energy utilization would critically contribute to observed neuroprotection with combined PG and TMZ treatment. Further exploration of this neuroprotective approach for post-recovery cognitive improvement is worth investigating.

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Molecular docking study.

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Drug repurposing.

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Combinatorial approach.

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Network Pharmacology.

Trimetazidine attenuates cyclophosphamide-induced cystitis by inhibiting TLR4-mediated NFκB signaling in mice

AIM

Cyclophosphamide (CP)-induced cystitis is a challenging clinical problem involving inflammation and dysfunction of bladder. Trimetazidine (TMZ) is an anti-anginal drug with anti-oxidant and anti-inflammatory properties. We aimed to investigate the protective effects of TMZ in CP-induced cystitis via inhibiting TLR4/NFκB signaling.

MAIN METHODS

Balb/c mice were administrated TMZ (10 or 20 mg/kg/day) intraperitoneally (i.p.) for 5 consecutive days before CP. On day 6, cystitis was induced by a single dose of CP (300 mg/kg, i.p.). Mesna (2-mercaptoethane sulfonate sodium; 30 mg/kg, i.p.) was administered 20 min before and at 4 and 8 h after the CP injection. After 24 h of cystitis induction, the bladders were removed for histopathological evaluation, contractility studies, biochemical analysis and western blotting. MTT assay was performed in a cancer cell line (MDA-MB-231) to evaluate the effect of TMZ on the cytotoxicity of CP.

KEY FINDINGS

CP-induced severe cystitis was confirmed by histological disturbances and the decrease in carbachol-evoked contractions of detrusor strips, which was partially improved by TMZ (20 mg/kg/day). SOD activity and GSH content were decreased whereas TNF-α and IL-1β levels were increased in the bladders of CP-treated mice, which were restored by TMZ or mesna. TMZ reduced the CP-induced increase in the protein expressions of caspase-3, TLR4 and phosphorylated-NFκB in bladder tissues. TMZ alone decreased the cell viability and TMZ also enhanced the cytotoxicity of CP.

SIGNIFICANCE

Our study provides the first preclinical evidence that TMZ attenuates CP-induced urotoxicity by enhancing anti-oxidant capacity and suppressing inflammation possibly via downregulating TLR4-mediated NFκB signaling while augmenting the cytotoxicity of CP.

Beneficial effect of trimetazidine on folic acid-induced acute kidney injury in mice: Role of HIF-1α/HO-1

Acute kidney injury (AKI) is a complex syndrome associated with a decrease in renal function and a significant impact on patient outcomes. Injection of folic acid (FA) in mice is used for studying the pathogenesis of AKI. This study investigated the impact of trimetazidine (a metabolic modulator-antianginal drug; TMZ), against FA-induced AKI. AKI was induced by FA (250 mg/kg, ip) in mice. Two doses of TMZ were administered orally for 10 days. Administration of TMZ at a high dose (20 mg/kg) exhibited significant decreases in the renal somatic index (RSI), serum levels of lactate dehydrogenase (LDH), creatinine (Cr), blood urea nitrogen (1), and proteins level in urine. Moreover, TMZ significantly increased creatinine clearance (CCr), serum albumin, urine creatinine, and urine urea levels. This improvement in markers of kidney damage was associated with marked renal antioxidant effects (↓NO and ↓lipid peroxidation, normalized reduced glutathione (GSH) level and superoxide dismutase (SOD) activity, and increased HIF-1α/HO-1 level). Furthermore, TMZ significantly decreased FA-induced expression of MPO and inflammatory cytokine IL-18, TNF-α, and NF-κB p65 subunit. Renal apoptosis, along with apoptotic markers, were enhanced by FA injection and suppressed by TMZ administration (↓Caspase-3, ↓Bax, and ↑Bcl2 expression). Finally, TMZ amended FA-induced histopathological changes in kidneys. By mitigating functional alteration, oxidative stress, and preventing the development of inflammatory and apoptosis signals, TMZ provides dose-dependent defense against FA-induced AKI mainly via stimulation of hypoxia-inducible factor-1 alpha (HIF-1α)/heme oxygenase-1 (HO-1) pathway.

The inhibitory effect of trimetazidine on detrusor contractility - a potential repositioning of trimetazidine for the treatment of overactive bladder

OBJECTIVES

This study aimed to identify the effect of trimetazidine (TMZ), an antianginal drug, on detrusor smooth muscle (DSM) contractility and its possible mechanisms of action.

METHODS

We performed in-vitro contractility studies on isolated mouse DSM strips and investigated the effect of TMZ on Ca2+ levels in fura-2-loaded A7r5 cells.

KEY FINDINGS

TMZ (300 or 1000 µM) inhibited carbachol (CCh)- and KCl-induced contractions and produced a concentration-dependent (10-1000 µM) relaxation in KCl-precontracted DSM strips. TMZ-induced relaxation was markedly decreased by BaCl2, an inward-rectifying K+ channel blocker, but was not altered by preincubation with tetraethylammonium, glibenclamide, 4-aminopyridine, propranolol, L-NAME or methylene blue. TMZ (300 or 1000 µM) reduced both the CaCl2-induced contraction of depolarized DSM strips under Ca2+-free conditions and the CCh-induced contraction of DSM strips preincubated with nifedipine in Ca2+-containing Krebs solution. Furthermore, TMZ (1000 µM) significantly decreased the Ca2+ levels in fura-2-loaded A7r5 cells.

CONCLUSIONS

TMZ decreased DSM contractility and caused a concentration-dependent relaxation of the tissue possibly through its actions on Ca2+ transients and K+ channels. Our results provide preclinical evidence that TMZ would be a potential candidate to treat disorders related to the overactivity of the bladder.

One-pot synthesis of fluorescent nitrogen and sulfur-carbon quantum dots as a sensitive nanosensor for trimetazidine determination

Water-soluble and highly stable N,S-doped CQDs (N,S-CQDs) were synthesized using a low-cost strategy with citric acid and thiosemicarbazide in one step for use as a fluorescent nanosensor. The achieved N,S-CQDs produced strong emission at 446 nm upon excitation at 370 nm and a high quantum yield of 58.5%. The quenching effect on the prepared N,S-CQDs was utilized for determination of trimetazidine (TMZ) spectrofluorimetrically over a wide linear range 0.04-0.5 μM (0.0106-0.133 μg ml^-1 ) and a low limit of detection of 0.01 μM (0.002 μg ml^-1 ). Furthermore, CDs were used as a simple and rapid fluorescent probe to determine TMZ in its pharmaceutical formulations as well as in human plasma. The method was tested in compliance with International Council for Harmonisation guidelines. The results obtained were compared statistically with those given for a reported method showing no significant variation regards accuracy and precision.

Trimetazidine Inhibits Renal Tubular Epithelial Cells to Mesenchymal Transition in Diabetic Rats via Upregulation of Sirt1

Trimetazidine (TMZ), as a metabolic regulator, is effective in treatment of coronary atherosclerotic heart disease with rare side effects in the clinic for long years. Interestingly, studies have shown that TMZ protects against several acute kidney injuries (AKI). However, the effect of TMZ on chronic kidney diseases (CKD) remains unknown. This study aimed to investigate the role of TMZ in diabetic nephropathy (DN) and its potential mechanisms. A rat model of DN was established in male Sprague-Dawley rats by streptozotocin (STZ) intraperitoneal injection. Experimental rats were separated into three groups: control, DN and DN + TMZ treatment. Metabolic parameters, pathological features and renal function markers were evaluated after 20 weeks of diabetes induction. In vitro experiments, the effect of TMZ on high fat and high glucose (HFG) induced or TGFβ1-induced epithelial-to-mesenchymal transition (EMT) was examined in HK-2 cells. Our results showed that TMZ could maintain renal function without affecting hemodynamic and plasma metabolic levels in diabetic rats. The effect was associated with a reversion of pathological progression of DN, especially for tubulointerstitial fibrosis. EMT is an important contributor to renal fibrosis. In this study, we investigated the role of TMZ in the process of EMT in DN. Mechanistically; TMZ attenuated HFG-induced EMT by relieving oxidative stress via deacetylation forkhead box O1 (FoxO1) in a Sirt1-dependent pathway. And it suppressed TGFβ1-induced EMT by deacetylating Smd4 in a Sirt1-dependent manner. Moreover, our study found that TMZ upregulated Sirt1 expression by increasing the expression of nicotinamide phosphoribosyl transferase (Nampt), which is a rate limiting enzyme for nicotinamide adenine dinucleotide (NAD⁺) generation by salvage pathway. And the increased NAD⁺ promoted Sirt1 expression. In conclusion, TMZ can prevent renal dysfunction and pathogenesis of tubulointerstitial fibrosis in DN, partly by inhibition of EMT via FoxO1/ROS pathway and TGFβ/Smad pathway in a Nampt/NAD⁺/Sirt1 dependent manner.

Protective effects of trimetazidine and coenzyme Q10 on cisplatin-induced cardiotoxicity by alleviating oxidative stress and mitochondrial dysfunction

Objective:

The objective of this study was to investigate the effects of trimetazidine (TMZ) and coenzyme Q10 (CoQ10) on cisplatin-induced cardiotoxicity in rat cardiomyocytes.

Methods:

Rat cardiomyocytes were isolated and subjected to cisplatin (200 µM) treatment with and without TMZ (200 µM) and CoQ10 (200 mg/L) pretreatment. The cell viability, apoptosis, oxidant and antioxidant indicators, and mitochondrial dysfunction were examined.

Results:

TMZ or CoQ10 significantly attenuated cisplatin-induced cell viability inhibition (p<0.01) and apoptosis (p<0.001), and the combined use of TMZ and CoQ10 pretreatment exerted a pronounced effect compared to the effects of using each of these agents individually (p<0.05). TMZ or CoQ10 inhibited the levels of reactive oxidative species (ROS, p<0.01) and malondialdehyde (MDA, p<0.001 and p<0.01, respectively), elevated the activities of antioxidant enzymes superoxide dismutase (SOD, p<0.01) and catalase (CAT, p<0.01 and p<0.05, respectively), evidently enhanced nuclear translocation of nuclear factor erythroid 2-related factor 2 (Nrf2, p<0.05), alleviated mitochondrial membrane potential (ΔΨm) loss (p<0.05), and down-regulated the release of cytochrome c (cyto-c) into the cytosol (p<0.01) in cisplatin-treated cells. The combined use of TMZ and CoQ10 treatment was more effective than using either agent alone (p<0.01 for ROS, MDA, CAT, and cytosolic cyto-c; p<0.05 for SOD, nuclear Nrf2, and ΔΨm loss).

Conclusion:

TMZ and CoQ10 showed protective effects against cisplatin-induced cardiotoxicity via attenuating oxidative stress.

Comparison of high-performance thin layer chromatography/UV-densitometry and UV-derivative spectrophotometry for the determination of trimetazidine in pharmaceutical formulations

New methods for assaying trimetazidine dihydrochloride on the basis of thin layer chromatography and spectrophotometry are proposed and compared in the paper. In HPTLC/UV-densitometry, separation is achieved by using a mobile phase composed of ammonia-methanol (30:70, V/V) on silica gel HPTLC plates F254. Quantification using a non-linear calibration curve is accomplished by densito-metric detection at 230 nm. Derivative spectrophotometric determination of trimetazidine dihydrochloride is carried out from the fourth derivative of the absorbance at 233 nm in peak-zero mode. Statistical comparison led to the conclusion that there is no significant difference between the two studied methods and, moreover, that they demonstrate satisfactory accuracy and precision for routine applications.

The effect of trimetazidine treatment in patients with type 2 diabetes undergoing percutaneous coronary intervention for AMI

PURPOSE

Trimetazidine (TMZ) improves clinical outcomes in patients with chronic heart failure and stable coronary artery disease. No study has yet evaluated the efficacy of TMZ in type 2 diabetes patients with acute myocardial infarction (AMI) undergoing Percutaneous Coronary Intervention (PCI). We performed this study to evaluate the efficacy TMZ in DM patients with AMI undergoing PCI, such as the effect on reductions in myocardial enzyme, improvements in liver function, modulation of glucose levels, and improvement in cardiac function.

METHODS

For this randomized study, we enrolled 173 AMI patients with type 2 diabetes undergoing PCI between January 1, 2014, and January 1, 2016. All patients received aspirin and ticagrelor upon admission and throughout their hospitalization. Patients in the experimental group were treated with a loading dose of 60mg TMZ at admission, and 20 mg TMZ three times a day thereafter. 89 patients were included in experimental group, and 84 patients were included in control group. All patients received PCI treatments. The endpoints evaluated were serum creatine kinase and its isoenzyme (CK and CK-MB), cardiac troponin I (cTNI), serum creatinine (Cr), serum urea, blood glucose, serum glutamic pyruvic transaminase (ALT), serum glutamic oxaloacetictransaminase (AST), left atrial dimension (LA), left ventricular ejection fraction (LVEF), left ventricular end-diastolic dimension (LVEDD), and cardiac output (CO).

FINDINGS

Compared with the control group, TMZ treatment significantly reduced CK and CK-MB on the second day in hospital ([797±582] vs. [1092±1114]; [80±60] vs. [105±100]; p=0.029, p=0.041, respectively), and cTNI after one and six days in hospital ([13.5±12.7] vs. [19.8±19.2]; [3.3±3.2] vs. [4.8±4.7]; two-tailed p=0.012). In addition, TMZ significantly lowered liver enzymes (ALT, AST) at 6days ([29.0±11.6] vs. [42.4±24.5]; [39.8±17.3] vs. [69.2±70.0]; two-tailed p=0.000), lowered glucose after 6days ([6.80±2.12] vs. [7.59±2.24]; p=0.019), and increased LVEF after ten to fourteen days ([58.4±8.6] vs. [54.9±8.4]; p=0.008). There were no significant effect on Cr and serum urea (p=0.988, p=0.569, respectively), nor on LA, LVEDD, and CO ([36.3±4.5] vs. [37.0±4.1], p=0.264; [52.0±4.9] vs. [53.1±4.6], p=0.128; [5.4±0.9] vs. [5.4±0.9], p=0.929, respectively).

IMPLICATIONS

Among type 2 diabetic patients with AMI undergoing PCI, TMZ significantly reduces serum myocardial enzyme, improves liver function, adjusts blood glucose and improves cardiac function.

Trimetazidine potentiates the antiepileptic activity and ameliorates the metabolic changes associated with pentylenetetrazole kindling in rats treated with valproic acid

Oxidative stress is implicated in epileptogenesis as well as in the metabolic changes associated with increased risk of atherosclerotic vascular disease in epilepsy. The present work investigated the impact of the antioxidant trimetazidine (TMZ) on the antiepileptic activity of valproic acid (VPA) and on the metabolic and histological changes in hippocampal, aortic, and hepatic tissues associated with epilepsy and (or) VPA. Rats were divided into non-pentylenetetrazole (non-PTZ) group subdivided into control and VPA-treated groups, and PTZ-treated group subdivided into PTZ, PTZ/VPA, PTZ/TMZ, and PTZ/VPA + TMZ groups. VPA treatment in PTZ rats resulted in an antioxidant effect with improvement in oxidative stress, metabolic and histopathological changes induced by PTZ in hippocampus, aortic, and hepatic tissues. TMZ exhibited anticonvulsant activity and potentiated the anticonvulsant effect of VPA. Combination of TMZ with VPA induced a greater reduction in oxidative stress, improvement in the metabolic and histopathological changes compared to VPA treatment. In contrast, VPA administration in non-PTZ-treated rats induced a pro-oxidative effect, associated with metabolic and histopathological changes in aortic and hepatic tissues. These findings suggest that co-administration of TMZ with VPA in epilepsy might antagonize not only the oxidative stress associated with epilepsy but might also counteract a potential pro-oxidative effect of VPA.

The risk of cardiovascular side effects with anti-anginal drugs

INTRODUCTION

Angina pectoris is a common presenting symptom of underlying coronary artery disease or reduced coronary flow reserve. Patients with angina have impaired quality of life; and need to be treated optimally with antianginal drugs to control symptoms and improve exercise performance. A wide range of antianginal medications are approved for the treatment of angina, and often more than one class of antianginal drugs are used to adequately control the symptoms. This expert opinion highlights the likely cardiac adverse effects of available antianginal drugs, and how to minimize these in individual patients and especially during combination treatment. Areas covered: All approved antianginal drugs, including the older and newly approved medications with different mechanism of action to the older drugs as well as some of the unapproved herbal medications. The safety profiles and potential cardiac side effects of these medications when used as monotherapy or as combination therapy are discussed and highlighted. Expert opinion: Because of the different cardiac safety profiles and possible side effects, we recommend selection of initial drug or adjustment of therapy based on the resting heart rate; blood pressure, hemodynamic status; and resting left ventricular function, concomitant medications and any associated comorbidities.

Trimetazidine prevents macrophage-mediated septic myocardial dysfunction via activation of the histone deacetylase sirtuin 1

BACKGROUND AND PURPOSE

Sepsis is a systemic inflammatory response accompanied by excessive production of inflammatory cytokines and cardiovascular dysfunction. Importantly, macrophage-derived pro-inflammatory agents play a key role in cardiovascular impairment in sepsis. Here we have investigated the effects of trimetazidine (TMZ) on pro-inflammatory responses of macrophages in endotoxin-induced myocardial dysfunction.

EXPERIMENTAL APPROACH

Mice pretreated with TMZ were injected i.p. with LPS and cardiac function evaluated. Levels of macrophage infiltration, macrophage inflammatory response and cardiomyocyte apoptosis were measured using immunohistochemical staining, elisa, real-time RT-PCR, Western blot, TUNEL and flow cytometry assays.

KEY RESULTS

Pretreatment with TMZ prevented LPS-induced myocardial dysfunction and apoptosis. TMZ also lowered levels of pro-inflammatory cytokines in serum and cardiac tissue and myocardial macrophage infiltration. Bone marrow transplantation indicated that TMZ alleviated LPS-induced myocardial dysfunction via decreasing macrophage infiltration. TMZ reduced expression of pro-inflammatory cytokines in LPS-stimulated cardiac and peritoneal macrophages. Co-culture of TMZ-pretreated macrophages with cardiomyocytes and conditioned media from TMZ-pretreated macrophages both decreased LPS-induced cardiomyocyte apoptosis. The anti-apoptosis effects of TMZ resulted from decrease of pro-inflammatory cytokines, partly due to normalizing the sirtuin 1 (Sirt1)/AMP-activated protein kinase (AMPK)/Nrf2/haem oxygenase-1 and Sirt1/PPARα pathways in macrophages. Cytokine secretion was also regulated by ROS, which were attenuated by TMZ via activation of Sirt1, AMPK and PPARα.

CONCLUSIONS AND IMPLICATIONS

TMZ protected against LPS-induced myocardial dysfunction and apoptosis, accompanied by inhibition of macrophage pro-inflammatory responses. Our studies suggest that TMZ might represent a novel therapeutic agent to prevent and treat sepsis-induced myocardial dysfunction.

Defining the role of trimetazidine in the treatment of cardiovascular disorders: some insights on its role in heart failure and peripheral artery disease

Trimetazidine is a cytoprotective drug whose cardiovascular effectiveness, especially in patients with stable ischemic heart disease, has been the source of much controversy in recent years; some have gone so far as to treat the medication as a ‘placebo drug’ whose new side effects, such as Parkinsonian symptoms, outweigh its benefits. This article is an attempt to present the recent key studies, including meta-analyses, on the use of trimetazidine in chronic heart failure, also in patients with diabetes mellitus and arrhythmia, as well as in peripheral artery disease. This paper also includes the most recent European Society of Cardiology guidelines, including those of 2013, on the use of trimetazidine in cardiovascular disease.

Trimetazidine demonstrated cardioprotective effects through mitochondrial pathway in a model of acute coronary ischemia

Myocardial ischemia affects mitochondrial function leading to ionic imbalance and susceptibility to ventricular fibrillation. Trimetazidine (TMZ), a metabolic agent, is clinically used as an anti-anginal therapy. This study was conducted to compare the effect of TMZ 20 mg immediate release (IR) and TMZ 35 mg modified release (MR), two bioequivalent marketed formulations of TMZ, on cardioprotection during acute ischemia in pigs. A 4-day oral treatment with TMZ 20 mg IR (800 mg, tid) or TMZ 35 mg MR (1,400 mg, bid) had no effect on ventricular fibrillation threshold (VFT) prior to ischemia but significantly prevented the decrease in VFT observed in placebo-treated groups after a 1-min left anterior descending coronary artery occlusion. This effect occurred without modifying cardiac hemodynamic and conduction parameters. In both TMZ-treated groups, a significant reduction of the ischemic area as well as a protection of cardiomyocytes were observed. Cardiac enzymatic activity (phosphorylase, succinate dehydrogenase, ATPase) was increased in TMZ-treated groups. Both formulations preserved mitochondrial structure and improved mitochondrial function as demonstrated by a twofold increase of oxidative phosphorylation, by a reduction of reactive oxygen species (ROS) production (>30 %) and by a trend to increase the mitochondrial calcium retention capacity. In this model of ischemia, both TMZ formulations, leading to equivalent TMZ plasma exposures, demonstrated similar cardioprotective effects. This protection could be attributed to a preservation of mitochondrial structure and function, which plays a central role in ATP and ROS production and consequently could be considered as a target of cardioprotection.

The effect of trimetazidine on cardiac function in diabetic patients with idiopathic dilated cardiomyopathy

AIMS

Trimetazidine is an anti-ischemic metabolic agent which improves myocardial glucose utilization. Whether it may improve cardiac function and physical tolerance in diabetic patients with idiopathic dilated cardiomyopathy is still not confirmed. In this study we have investigated the effectiveness of trimetazidine in these patients.

MAIN METHODS

Volunteers with diabetes and idiopathic dilated cardiomyopathy were recruited for participation in this study. Patients were randomized into two groups. One group received trimetazidine (20mg, t.i.d.) for 6 months (n=40), while another group received a placebo during the same period (n=40). All patients received an echocardiographic examination, 6-minute walk test and an inflammation biochemical analysis (C reactive protein) at baseline and after 6 months of treatment.

KEY FINDINGS

No significant adverse events or changes in clinical or biochemical parameters were detected through the study. After 6 months, TMZ-treated patients had a significant improvement in systolic function as compared with control patients associated with an increased ratio of E/A. C reactive protein concentrations remained stable throughout the study in trimetazidine group at baseline and at the 6 month on follow up. In comparison, it increased significantly in the control group at the 6-month follow up. The NT-pro BNP levels did not change in the control group, whereas they significantly decreased in the trimetazidine group. The physical activity tolerance level improved in the trimetazidine group compared to the control group.

SIGNIFICANCE

Trimetazidine treatment was associated with a significant improvement of cardiac function and physical tolerance. Results also suggested that the inflammatory response was decreased in trimetazidine group as compared with control patients.

S 35171 exerts protective effects in spontaneously hypertensive stroke-prone rats by preserving mitochondrial function

S 35171 is one of a family of compounds that have been designed to protect mitochondrial function. We tested the hypothesis that S 35171 exerts protective effects in spontaneously hypertensive stroke-prone rats (SHRSPs), an animal model developing spontaneous brain damage preceded by proteinuria and systemic inflammation revealed by the urinary accumulation of acute-phase proteins (APPs) originating in the liver. Male SHRSPs fed a permissive diet received vehicle or S 35171 (10 mg/kg/day) started simultaneously with a high-sodium diet (group A) or after the establishment of proteinuria (group B). The drug delayed urinary APPs accumulation and the appearance of magnetic resonance imaging (MRI)-monitored brain lesions (after 62+/-3 days in group A, and 51+/-2 days in controls, P<0.01). The delay was more pronounced in group B as 30% of the animals survived the entire 90-day experimental period without brain abnormality. Proteomic analysis showed no significant alteration in the expression pattern of brain mitochondrial proteins, but the liver mitochondrial levels of carbamoylphosphate synthase I (CPS-I), an enzyme involved in urea metabolism) and the antioxidant peroxiredoxin-3 spot were affected by hypertension and S 35171. Stress reduces CPS-I and induces the peroxiredoxin-3 spot, whereas S 35171 brought about normal CPS-I expression and a 12-fold higher level of the peroxiredoxin-3 spot. As both enzymes are involved in maintaining mitochondrial functions, their increased expression after S 35171 treatment may be responsible for delaying the pathological condition that leads to the development of brain damage in SHRSPs.