Evidence for a mitochondrial impact of trimetazidine during cold ischemia and reperfusion

New insights on pharmacological and therapeutic potentials of trimetazidine beyond anti-anginal drug: A comprehensive review

Trimetazidine (TMZ) is a beneficial and well-tolerable anti-anginal drug which has protective action towards ischemia and reperfusion injury. TMZ performs its anti-ischemic effect by modifying cardiac metabolism without shifting the hemodynamic functions, so it represents an outstanding complementary perspective to the general angina treatment. TMZ possesses a positive impact on the inflammatory profile, and also endothelial function furthermore displays various benefits through minimising the number, as well as the intensity of angina strikes and ameliorating the clinical indication and symptoms of myocardium ischemia. It is administrated as monotherapy along with a combination of different antianginal drugs. Apart from anti-angina action, in recent years TMZ has shown various pharmacological activities such as neuroprotective, renal protective, hepato-protective, cardio-protective effects, and other beneficial pharmacological activities. We select to write the present review article to cover the different pharmacological and therapeutic potentials of TMZ.

Effect of PERLA®, a new cold-storage solution, on oxidative stress injury and early graft function in rat kidney transplantation model

BACKGROUND

The composition of organ preservation solutions is crucial for maintaining graft integrity and early graft function after transplantation. The aim of this study is to compare new organ preservation solution PERLA® with the gold standard preservation solution University of Wisconsin (UW) regarding oxidative stress and early graft injury.

METHODS

In order to assess oxidative stress after cold storage, kidney grafts have been preserved for 18 h at 4° C in either UW solution or PERLA® solution and then assessed for oxidative stress injury (protocol 1). To assess kidney injuries and oxidative stress after reperfusion, rat kidneys were harvested, stored in cold UW or in PERLA® solutions for 18 h at 4 °C and then transplanted heterotopically for 6 h (protocol 2). PERLA® is a high Na+/low K+ solution including PEG-35 (1 g/L), trimetazidine (1 µM), carvedilol (10 µM) and tacrolimus (5 µM).

RESULTS

Our results showed that preservation of kidneys in PERLA® solution significantly attenuates oxidative stress parameters after cold storage and reperfusion. We found a significant decrease in oxidative damage indicators (MDA, CD and CP) and a significant increase in antioxidant indicators (GPx, GSH, CAT, SOD and PSH). Moreover, PERLA® solution decreased kidney injury after reperfusion (creatinine, LDH and uric acid).

CONCLUSION

PERLA® solution was more effective than UW storage solution in preserving rat's kidney grafts.

A Potential Route to Reduce Ischemia/Reperfusion Injury in Organ Preservation

The pathophysiological process of ischemia and reperfusion injury (IRI), an inevitable step in organ transplantation, causes important biochemical and structural changes that can result in serious organ damage. IRI is relevant for early graft dysfunction and graft survival. Today, in a global context of organ shortages, most organs come from extended criteria donors (ECDs), which are more sensitive to IRI. The main objective of organ preservation solutions is to protect against IRI through the application of specific, nonphysiological components, under conditions of no blood or oxygen, and then under conditions of metabolic reduction by hypothermia. The composition of hypothermic solutions includes osmotic and oncotic buffering components, and they are intracellular (rich in potassium) or extracellular (rich in sodium). However, above all, they all contain the same type of components intended to protect against IRI, such as glutathione, adenosine and allopurinol. These components have not changed for more than 30 years, even though our knowledge of IRI, and much of the relevant literature, questions their stability or efficacy. In addition, several pharmacological molecules have been the subjects of preclinical studies to optimize this protection. Among them, trimetazidine, tacrolimus and carvedilol have shown the most benefits. In fact, these drugs are already in clinical use, and it is a question of repositioning them for this novel use, without additional risk. This new strategy of including them would allow us to shift from cold storage solutions to cold preservation solutions including multitarget pharmacological components, offering protection against IRI and thus protecting today's more vulnerable organs.

Preservation Solutions for Kidney Transplantation: History, Advances and Mechanisms

Solid organ transplantation was one of the greatest medical advances during the past few decades. Organ preservation solutions have been applied to diminish ischemic/hypoxic injury during cold storage and improve graft survival. In this article, we provide a general review of the history and advances of preservation solutions for kidney transplantation. Key components of commonly used solutions are listed, and effective supplementations for current available preservation solutions are discussed. At cellular and molecular levels, further insights were provided into the pathophysiological mechanisms of effective ingredients against ischemic/hypoxic renal injury during cold storage. We pay special attention to the cellular and molecular events during transplantation, including ATP depletion, acidosis, mitochondrial dysfunction, oxidative stress, inflammation, and other intracellular mechanisms.

Protection Against Cold Storage-Induced Renal Tubular Cell Apoptosis

BACKGROUND

Prolonged cold storage (CS) of donor kidneys is associated with tubular cell apoptosis and caspase-3 activation. We have previously shown that pancaspase inhibition prevents CS-associated tubular apoptosis. Because of the nonspecific nature of pancaspase inhibitors, which block all caspases including proinflammatory caspase-1, the effect of specific caspase-3 inhibition during CS is unknown. X-linked inhibitor of apoptosis (XIAP) is the most potent naturally occurring specific inhibitor of caspase-3. We hypothesized that prolonged CS would decrease XIAP, whereas upregulation of XIAP with the novel compound UCF-101 would protect against caspase-3 activation and tubular cell apoptosis.

METHODS

LLC-PK1 tubular cells and whole kidneys from C57BL/6 mice were subjected to prolonged CS with or without UCF-101, and examined for XIAP, caspase-3, and tubular apoptosis.

RESULTS

Tubular cells subjected to prolonged CS in vitro demonstrated significantly decreased XIAP and significantly increased apoptosis, caspase-3 protein and activity. UCF-101 treatment significantly increased XIAP, significantly decreased capsase-3 protein and activity, and protected against apoptosis. To determine the therapeutic significance, whole kidneys were subjected to prolonged CS with UCF-101. UCF-101 significantly increased XIAP in donor kidneys and protected against apoptosis.

CONCLUSIONS

Prolonged CS of tubular cells in vitro and whole mouse kidneys ex vivo is associated with loss of XIAP and subsequent tubular cell apoptosis. UCF-101 protects against the loss of XIAP during prolonged CS both in vitro and ex vivo, and is associated with significantly reduced tubular cell apoptosis. UCF-101 may represent an attractive approach to improve organ preservation.

Mitochondrial proteomes of porcine kidney cortex and medulla: foundation for translational proteomics

BACKGROUND

Emerging evidence has linked mitochondrial dysfunction to the pathogenesis of many renal disorders, including acute kidney injury, sepsis and even chronic kidney disease. Proteomics is a powerful tool in elucidating the role of mitochondria in renal pathologies. Since the pig is increasingly recognized as a major mammalian model for translational research, the lack of physiological proteome data of large mammals prompted us to examine renal mitochondrial proteome in porcine kidney cortex and medulla

METHODS

Kidneys were obtained from six healthy pigs. Mitochondria from cortex and medulla were isolated using differential centrifugation and proteome maps of cortical and medullar mitochondria were constructed using two-dimensional gel electrophoresis (2DE). Protein spots with significant difference between mitochondrial fraction of renal cortex and medulla were identified by mass spectrometry.

RESULTS

Proteomic analysis identified 81 protein spots. Of these spots, 41 mitochondrial proteins were statistically different between renal cortex and medulla (p < 0.05). Protein spots containing enzymes of beta oxidation, amino acid metabolism, and gluconeogenesis were predominant in kidney cortex mitochondria. Spots containing tricarboxylic acid cycle enzymes and electron transport system proteins, proteins maintaining metabolite transport and mitochondrial translation were more abundant in medullar mitochondria.

CONCLUSION

This study provides the first proteomic profile of porcine kidney cortex and medullar mitochondrial proteome. Different protein expression pattern reflects divergent functional metabolic role of mitochondria in various kidney compartments. Our study could serve as a useful reference for further porcine experiments investigating renal mitochondrial physiology under various pathological states.

Attenuation of endoplasmic reticulum stress and mitochondrial injury in kidney with ischemic postconditioning application and trimetazidine treatment

BACKGROUND

Endoplasmic reticulum (ER) and mitochondria have been implicated in the pathology of renal ischemia/reperfusion (I/R). In the present study, we investigated whether the use of ischemic postconditioning (IPostC) and trimetazidine (TMZ) separately or combined could reduce ER stress and mitochondria damage after renal ischemia.

METHODS

Kidneys of Wistar rats were subjected to 60-min of warm ischemia followed by 120-min of reperfusion (I/R group, n = 6), or to 6 cycles of ischemia/reperfusion (10-s each cycle) just after 60-min of warm ischemia (IPostC group, n = 6), or to i.p. injection of TMZ (3 mg/kg) 30-min before ischemia (TMZ group, n = 6), or to the combination of both treatments (IPostC+TMZ group, n = 6). The results of these experimental groups were compared to those of a sham-operated group in which rat renal pedicles were only dissected. Sodium reabsorption rate, creatinine clearance lactate deshydrogenase (LDH) activity in plasma, and concentration of malonedialdehyde (MDA) in tissue were determined. In addition, Western blot analysis was performed to identify the amounts of cytochrome c, c-JunNH2-terminal kinase (JNK), voltage-dependent anion channel (VDAC), glycogen synthase kinase 3-beta (GSK3-β), and ER stress parameters.

RESULTS

IPostC or/and TMZ significantly decreased cytolysis, oxidative stress and improved renal function in comparison to I/R group. IPostC but not TMZ significantly attenuated ER stress parameters versus I/R group. Indeed, it down-regulated the glucose-regulated protein 78 (GRP78), the activating transcription factor 4 (ATF4), the RNA activated protein kinase (PKR)-like ER kinas (PERK), the X box binding protein-1 (XBP-1) and the caspase12 protein levels. TMZ treatment significantly augmented GSK3-β phosphorylation and reduced levels of cytochrome c and VDAC phosphorylation in comparison to IPostC application. The combination of both treatments gave a synergetic effect. It significantly improved the survival rate, attenuated cytolysis, oxidative stress and improved renal function.

CONCLUSION

This study revealed that IPostC protects kidney from I/R injury by suppressing ER stress while the beneficial effects of TMZ are mediated by mitochondria protection. The combination of both treatments ameliorated functional recovery.

Pharmacological strategies against cold ischemia reperfusion injury

IMPORTANCE OF THE FIELD

Good organ preservation is a determinant of graft outcome after revascularization. The necessity of increasing the quality of organ preservation, as well as of extending cold storage time, has made it necessary to consider the use of pharmacological additives.

AREAS COVERED IN THIS REVIEW

The complex physiopathology of cold-ischemia-reperfusion (I/R) injury--and in particular cell death, mitochondrial injury and endoplasmic reticulum stress--are reviewed. Basic principles of the formulation of the different preservation solutions are discussed.

WHAT THE READER WILL GAIN

Current strategies and new trends in static organ preservation using additives such as trimetazidine, polyethylene glycols, melatonin, trophic factors and endothelin antagonists in solution are presented and discussed. The benefits and mechanisms responsible for enhancing organ protection against I/R injury are also discussed. Graft preservation was substantially improved when additives were added to the preservation solutions.

TAKE HOME MESSAGE

Enrichment of preservation solutions by additives is clinically useful only for short periods. For longer periods of cold ischemia, the use of such additives becomes insufficient because graft function deteriorates as a result of ischemia. In such conditions, the preservation strategy should be changed by the use of machine perfusion in normothermic conditions.

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

Trimetazidine (TMZ) is an effective and well-tolerated antianginal drug that possesses protective properties against ischemia-induced heart injury. Growing interest in metabolic modulation in recent years urged an up-to-date review of the literature on TMZ. This review consists of two major sections: (1) comprehensive and critical information about the pharmacological effects, mechanism of action, pharmacokinetics, side effects, and current usage of TMZ, and (2) developments in analytical techniques for the determination of the drug in raw material, pharmaceutical dosage forms, and biological samples.

Suppression of angioplasty-related inflammation by pre-procedural treatment with trimetazidine

Percutaneous transluminal coronary angioplasty (PTCA) has been recognized as a reliable treatment procedure for acute reversible ischemia and reperfusion. Ischemic reperfusion cycle in PTCA leads to the systemic inflammation and extensive tissue injury by the production of reactive oxygen species including nitric oxide (NO) radicals. In patients with coronary artery disease, undergoing PTCA, the effects of trimetazidine (TMZ), a piperazine-derivative anti-anginal drug, were studied on several indirect markers of systemic inflammatory response: tumor necrosis factor-alpha (TNF-alpha), C-reactive protein (CRP) and NO products (nitrite and nitrate). Patients (n = 11 each group) were untreated or pre-treated with TMZ (20 mg per orally three times a day), begun three days prior to PTCA, and marker levels were measured before the start of TMZ therapy (baseline), just before PTCA (0 hr), and 4, 24, and 48 hrs after PTCA. The baseline levels of markers were not significantly different between the untreated and pre-treated patients. In contrast, all parameters were lower in the TMZ-treated group than those in the matched control group in the pre- and post-angioplasty periods. Interestingly, in the TMZ group, CRP and nitrite levels were significantly lower than in the control group at each time point of the pre- and post-angioplasty periods, but the TNF-alpha levels were significantly decreased only in the post-angioplasty period. Pre-procedural treatment with oral TMZ for three days significantly suppressed the elevation of inflammatory markers before and shortly after PTCA. We suggest the usefulness of TMZ in preventing inflammatory cardiovascular events after PTCA.

Effect of trimetazidine on the nucleotide profile in rat kidney with ischemia-reperfusion injury

Ischemia-reperfusion injury is often responsible for delayed graft function after transplantation. Trimetazidine (TMZ) is an antioxidant agent used to protect grafts from ischemia-reperfusion injury. The aim of the study was to examine the effect of TMZ on nucleotide profile in rat kidney with ischemia-reperfusion injury. The study was carried out on Wistar rats divided into two groups: animals treated with TMZ and control group receiving placebo. TMZ 10mg/kg/day was administrated for 30 days. Concentrations of adenosine triphosphate (ATP), adenosine diphosphate (ADP), adenosine monophosphate (AMP), adenosine (Ado), guanosine triphosphate (GTP), guanosine diphosphate (GDP), guanosine monophosphate (GMP), guanosine (Guo), inosine monophosphate (IMP), inosine (Ino), hypoxanthine (Hyp), xanthine (Xan), uric acid (UA), uridine (Urd), nicotinamide adenine dinucleotide (NAD) and nicotinamide adenine dinucleotide phosphate (NADP) were determined in kidney tissues after ischemia-reperfusion using HPLC. The total adenine nucleotide concentration (TAN) and adenylate energy charge (AEC) were also determined. Moreover the kidneys were evaluated histologically. Tissue concentrations of ATP, ADP, AMP, TAN and AEC were significantly increased in kidneys from rats treated with TMZ in comparison with rats receiving placebo. Concentrations of products of nucleotide degradation: inosine (Ino), guanosine (Guo) and uridine (Urd), as well as oxypurines: Hyp and Xan, were significantly decreased in rats treated with trimetazidine. Moreover, significantly less pronounced acute tubular necrosis was observed in kidneys of rats treated with TMZ. These results suggest that trimetazidine protects against dephosphorylation of nucleotides and ischemic damage.

Pharmacological investigation of trimetazidine in models of inflammation, pain and gastric injury in rodents

The antinociceptive, anti-inflammatory and gastric effects of trimetazidine (2,3,4-trimethoxybenzyl-piperazine dihydrochloride), a novel anti-ischaemic compound, were evaluated in various animal models. In acute pain models, namely acetic acid-induced writhing, hot-plate assay, tail electric stimulation test, capsaicin-induced pain and the formalin test, trimetazidine (1.8-7.2 mg/kg, i.p.) showed marked antinociceptive effects. Trimetazidine did not produce any behavioural impairment as revealed by the mouse rotarod. The inhibition of writhing response by trimetazidine was reduced by yohimbine, theophylline (and to a certain extent by sulpiride) but not by prazosin, guanethidine, naloxone, atropine, propranolol, haloperidol, domperidone, clozapine, glibenclamide or caffeine. The carrageenan-evoked acute paw oedema was reduced by 19.2-21.2 and 17-18.6% by 3.6 and 7.2 mg/kg trimetazidine, respectively. The drug did not alter the oedema-suppressive effect of indomethacin or dexamethasone, but reduced that of rofecoxib. Trimetazidine at 7.2 mg/kg reduced immobility time in Porsolt's forced-swimming test by 28.9%. The acute gastric mucosal lesions evoked by indomethacin in the rat were inhibited in a dose-dependent manner by co-administration of trimetazidine. In anesthetized rats, trimetazidine potentiated the gastric acid secretory response. This study indicates that trimetazidine possesses antinociceptive and gastric protective properties. The antinociceptive properties of trimetazidine are likely to be centrally mediated, but do not involve opioid pathways.

[Ischemia-reperfusion injury during experimental heart transplantation. Evaluation of trimetazidine's cytoprotective effect]

INTRODUCTION AND OBJECTIVES

The objectives of this study were to analyze the ischemia-reperfusion injury due to free radicals that occurs during heart transplantation and to determine the potential cytoprotective effect of trimetazidine.

MATERIAL AND METHOD

A total of 21 orthotopic heart transplantations were performed in pigs. We divided the experimental animals into 2 groups: in group A (n=11),standard myocardial protection was used; in group B (n=10), trimetazidine was added to the cardioplegic solution used to protect the donor heart and to the solution administered to the recipient prior to release of the aortic clamp (trimetazidine, 10(-5) mol/L), and recipients were pretreated with trimetazidine, 2.5 mg/kg. Blood samples were taken from the recipients coronary sinus at three times: at baseline, during ischemia, and during reperfusion. We measured the levels of malondialdehyde, a marker of lipid peroxidation, and of several antioxidants: glutathione peroxidase, glutathione reductase, superoxide dismutase, alpha-tocopherol, and retinol. The total antioxidant status was also determined.

RESULTS

Malondialdehyde production and enzymatic antioxidant activity rose during ischemia and reperfusion, while the retinol level decreased. The increases in malondialdehyde level and glutathione peroxidase activity that occurred between baseline and reperfusion were significantly higher in group A. CONCLUSIONS. The degree of lipid peroxidation and the level of activity of intracellular antioxidant mechanisms increased progressively throughout transplantation. Trimetazidine had a cytoprotective effect. It ameliorated free radical-induced reperfusion injury and modified the response pattern of several defense mechanisms.