Meldonium, as a potential neuroprotective agent, promotes neuronal survival by protecting mitochondria in cerebral ischemia-reperfusion injury.

BACKGROUND: Stroke is a globally dangerous disease capable of causing irreversible neuronal damage with limited therapeutic options. Meldonium, an inhibitor of carnitine-dependent metabolism, is considered an anti-ischemic drug. However, the mechanisms through which meldonium improves ischemic injury and its potential to protect neurons remain largely unknown. METHODS: A rat model with middle cerebral artery occlusion (MCAO) was used to investigate meldonium's neuroprotective efficacy in vivo. Infarct volume, neurological deficit score, histopathology, neuronal apoptosis, motor function, morphological alteration and antioxidant capacity were explored via 2,3,5-Triphenyltetrazolium chloride staining, Longa scoring method, hematoxylin and eosin staining, terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling assay, rotarod test, transmission electron microscopy and Oxidative stress index related kit. A primary rat hippocampal neuron model subjected to oxygen-glucose deprivation reperfusion was used to study meldonium's protective ability in vitro. Neuronal viability, mitochondrial membrane potential, mitochondrial morphology, respiratory function, ATP production, and its potential mechanism were assayed by MTT cell proliferation and cytotoxicity assay kit, cell-permeant MitoTracker® probes, mitochondrial stress, real-time ATP rate and western blotting. RESULTS: Meldonium markedly reduced the infarct size, improved neurological function and motor ability, and inhibited neuronal apoptosis in vivo. Meldonium enhanced the morphology, antioxidant capacity, and ATP production of mitochondria and inhibited the opening of the mitochondrial permeability transition pore in the cerebral cortex and hippocampus during cerebral ischemia-reperfusion injury (CIRI) in rats. Additionally, meldonium improved the damaged fusion process and respiratory function of neuronal mitochondria in vitro. Further investigation revealed that meldonium activated the Akt/GSK-3ß signaling pathway to inhibit mitochondria-dependent neuronal apoptosis. CONCLUSION: Our study demonstrated that meldonium shows a neuroprotective function during CIRI by preserving the mitochondrial function, thus prevented neurons from apoptosis.

Safety of temozolomide use in adult patients with renal dysfunction.

PURPOSE: Temozolomide (TMZ), a cytotoxic DNA alkylating agent, is the main chemotherapy used for the treatment of high grade astrocytomas. The active alkylator, methylhydrazine, is not recovered in urine and thus renal function is not expected to affect clearance. Prescribing information for TMZ states pharmacokinetics have not been studied in adults with poor renal function, eGFR < 36 mL/min/1.73 m2. We reviewed our clinical experience with TMZ in patients with impaired renal function to evaluate safety of administering full dose TMZ. METHODS: The primary endpoint was to characterize the incidence and severity of thrombocytopenia in patients with eGFR < 60 mL/min/1.73 m2 who received TMZ for treatment of high grade gliomas (HGG) or primary CNS lymphoma (PCNSL). Secondary endpoints included incidence and severity of neutropenia, lymphopenia hepatotoxicity, and number of TMZ cycles administered. Medical records of patients with HGG or PCNSL treated with TMZ from October 1, 2016-September 30, 2019 were accessed to identify cases for this study. RESULTS: Thirty-two patients were eligible for this study. Of the seven patients with eGFR < 36 mL/min/1.73m2, 38/39 cycles (97%) were completed without grade 3-4 thrombocytopenia. No patients experienced grade 3-4 neutropenia, and grade 3-4 lymphopenia occurred in 5 cycles (15%). One patient discontinued TMZ 7 days prior to completion of radiation due to thrombocytopenia. CONCLUSION: Hematologic toxicity in patients with severe renal dysfunction, eGFR < 36 mL/min/1.73m2, is similar to that of patients with normal renal function. Severe renal impairment does not preclude use of temozolomide, but cautious monitoring of blood counts is warranted.

Hyperpolarized magnetic resonance shows that the anti-ischemic drug meldonium leads to increased flux through pyruvate dehydrogenase in vivo resulting in improved post-ischemic function in the diabetic heart.

The diabetic heart has a decreased ability to metabolize glucose. The anti-ischemic drug meldonium may provide a route to counteract this by reducing l-carnitine levels, resulting in improved cardiac glucose utilization. Therefore, the aim of this study was to use the novel technique of hyperpolarized magnetic resonance to investigate the in vivo effects of treatment with meldonium on cardiac metabolism and function in control and diabetic rats. Thirty-six male Wistar rats were injected either with vehicle, or with streptozotocin (55 mg/kg) to induce a model of type 1 diabetes. Daily treatment with either saline or meldonium (100 mg/kg/day) was undertaken for three weeks. in vivo cardiac function and metabolism were assessed with CINE MRI and hyperpolarized magnetic resonance respectively. Isolated perfused hearts were challenged with low-flow ischemia/reperfusion to assess the impact of meldonium on post-ischemic recovery. Meldonium had no significant effect on blood glucose concentrations or on baseline cardiac function. However, hyperpolarized magnetic resonance revealed that meldonium treatment elevated pyruvate dehydrogenase flux by 3.1-fold and 1.2-fold in diabetic and control animals, respectively, suggesting an increase in cardiac glucose oxidation. Hyperpolarized magnetic resonance further demonstrated that meldonium reduced the normalized acetylcarnitine signal by 2.1-fold in both diabetic and control animals. The increase in pyruvate dehydrogenase flux in vivo was accompanied by an improvement in post-ischemic function ex vivo, as meldonium elevated the rate pressure product by 1.3-fold and 1.5-fold in the control and diabetic animals, respectively. In conclusion, meldonium improves in vivo pyruvate dehydrogenase flux in the diabetic heart, contributing to improved cardiac recovery after ischemia.

Protective Effects of Meldonium in Experimental Models of Cardiovascular Complications with a Potential Application in COVID-19.

Right ventricular (RV) and left ventricular (LV) dysfunction is common in a significant number of hospitalized coronavirus disease 2019 (COVID-19) patients. This study was conducted to assess whether the improved mitochondrial bioenergetics by cardiometabolic drug meldonium can attenuate the development of ventricular dysfunction in experimental RV and LV dysfunction models, which resemble ventricular dysfunction in COVID-19 patients. Effects of meldonium were assessed in rats with pulmonary hypertension-induced RV failure and in mice with inflammation-induced LV dysfunction. Rats with RV failure showed decreased RV fractional area change (RVFAC) and hypertrophy. Treatment with meldonium attenuated the development of RV hypertrophy and increased RVFAC by 50%. Mice with inflammation-induced LV dysfunction had decreased LV ejection fraction (LVEF) by 30%. Treatment with meldonium prevented the decrease in LVEF. A decrease in the mitochondrial fatty acid oxidation with a concomitant increase in pyruvate metabolism was noted in the cardiac fibers of the rats and mice with RV and LV failure, respectively. Meldonium treatment in both models restored mitochondrial bioenergetics. The results show that meldonium treatment prevents the development of RV and LV systolic dysfunction by enhancing mitochondrial function in experimental models of ventricular dysfunction that resembles cardiovascular complications in COVID-19 patients.

News and views in myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS): The role of co-morbidity and novel treatments.

Though affecting many thousands of patients, myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) should be considered an orphan disease, since the cause remains elusive and no treatment is available that can provide complete cure. There is reasonable insight into the pathogenesis of signs and symptoms, and treatments specifically directed to immunological, inflammatory and metabolic processes offer relief to an increasing number of patients. Particular attention is given to the importance of co-morbidity requiring appropriate therapy. Promising results are obtained by treatment with Metformin, or possibly Momordica charantia extract, which will correct insulin resistance, with Meldonium improving the transportation of glucose into the mitochondria, with sodium dichloroacetate activating pyruvate dehydrogenase, and with nutraceutical support reducing oxidative and inflammatory impairment.

Normalization of heart rate variability with taurine and meldonium complex in post-infarction patients with type 2 diabetes mellitus.

The purpose of this study is to scrutiny the Dynamics of heart rate variability (HRV) in patients with PICS with 2nd type DM against the background of Taurine (TN) and meldonium (ME). The results of the investigations prove the decrease of the oxidative stress, which is basis of DACN, under the influence of sulfur-containing amino acid taurine (TN), and meldonium (ME) - a competitive inhibitor of gamma-butyrobetaine hydroxylase. Biochemical mechanisms of synergistic action of ME and TN are also described. The results of the studies of 98 patients with PICS and concomitant 2nd type diabetes mellitus were analyzed. They were distributed by simple randomization method into two groups, comparable according to age and sex: the main group (MG) (n = 68): and group of comparison (GoC) (n = 30). HRV was evaluated twice daily at the Cardiosense HMEGG system: at baseline and after 12 weeks of treatment. For the assessment of HRV the frequency and spectral parameters were used. While evaluating the different methods of treatment, their influence on the range of spectral and time indices of HRV was determined (p = 0.001 by the criterion of Kruskall-Wallis). It was learned that the combined application of ME and TN gives a statistically significant (p <0.01) increase of SDNN, HF at night, pNN - on 50% by day (p <0.01, p <0.001 and p <0.01 respectively), and statistically significant decrease in LF at night, compared to GHG.

The Effects of Meldonium on the Renal Acute Ischemia/Reperfusion Injury in Rats.

Acute renal ischemia/reperfusion (I/R) injury is a clinical condition that is challenging to treat. Meldonium is an anti-ischemic agent that shifts energy production from fatty acid oxidation to less oxygen-consuming glycolysis. Thus, in this study we investigated the effects of a four-week meldonium pre-treatment (300 mg/kg b.m./day) on acute renal I/R in male rats (Wistar strain). Our results showed that meldonium decreased animal body mass gain, food and water intake, and carnitine, glucose, and lactic acid kidney content. In kidneys of animals subjected to I/R, meldonium increased phosphorylation of mitogen-activated protein kinase p38 and protein kinase B, and increased the expression of nuclear factor erythroid 2-related factor 2 and haeme oxygenase 1, causing manganese superoxide dismutase expression and activity to increase, as well as lipid peroxidation, cooper-zinc superoxide dismutase, glutathione peroxidase, and glutathione reductase activities to decrease. By decreasing the kidney Bax/Bcl2 expression ratio and kidney and serum high mobility group box 1 protein content, meldonium reduced apoptotic and necrotic events in I/R, as confirmed by kidney histology. Meldonium increased adrenal noradrenaline content and serum, adrenal, hepatic, and renal ascorbic/dehydroascorbic acid ratio, which caused complex changes in renal lipidomics. Taken together, our results have confirmed that meldonium pre-treatment protects against I/R-induced oxidative stress and apoptosis/necrosis.

Meldonium improves Huntington's disease mitochondrial dysfunction by restoring peroxisome proliferator-activated receptor γ coactivator 1α expression.

Mitochondrial dysfunction seems to play a fundamental role in the pathogenesis of neurodegeneration in Huntington's disease (HD). We assessed possible neuroprotective actions of meldonium, a small molecule affecting mitochondrial fuel metabolism, in in vitro and in vivo HD models. We found that meldonium was able to prevent cytotoxicity induced by serum deprivation, to reduce the accumulation of mutated huntingtin (mHtt) aggregates, and to upregulate the expression of peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α) in mHTT-expressing cells. The PGC-1α increase was accompanied by the increment of mitochondrial mass and by the rebalancing of mitochondrial dynamics with a promotion of the mitochondrial fusion. Meldonium-induced PGC-1α significantly alleviated motor dysfunction and prolonged the survival of a transgenic HD Drosophila model in which mHtt expression in the nervous system led to progressive motor performance deficits. Our study strongly suggests that PGC-1α, as a master coregulator of mitochondrial biogenesis, energy homeostasis, and antioxidant defense, is a potential therapeutic target in HD.

[Efficacy of Short-Term Therapy With Meldonium in Patients With Chronic Heart Failure of Ischemic Etiology and Type 2 Diabetes Mellitus].

PURPOSE: to assess efficacy and endotheliotropic properties of short-term addition of meldonium to basic therapy of patients with chronic ischemic heart failure and type 2 diabetes. RESULTS AND CONCLUSION: The study demonstrated the ability of meldonium to significantly improve endothelial function and the state of microcirculatory vascular bed, as well as to influence beneficially heart rate variability.

CLINICAL EFFICACY OF S-ADENOSYLMETHIONINE IN PATIENTS WITH NON-ALCOHOLIC STEATOHEPATITIS AND CHRONIC KIDNEY DISEASE I-II STAGE.

The article presents a theoretical generalization of the results of the clinical efficacy of S-adenosylmethionine in patients with non-alcoholic steatohepatitis (NASH) in comorbidity with obesity and chronic kidney disease (CKD) of the 1st-2nd stages. The objective of the article was to determine the likely effect of S-adenosylmethionine and Meldonium on the clinical course of non-alcoholic steatohepatitis (NASH) and chronic kidney disease (CKD) of the I-II stages. We examined 75 patients with NASH with comorbid obesity I degree and CKD I and II dgrees. To determine the efficacy of the treatment, 3 groups of patients were randomized according to age, sex, degree of obesity, activity of the cytolytic syndrome of NASH and the stage of the CKD. SAM possesses powerful membrane-stabilizing properties, stably eliminates the manifestations of cytolysis, cholestasis, mesenchymal-inflammatory syndrome, increases the albumin-synthesizing function of the liver in patients with NASH and prevents the loss of albumins in the conditions of CKD І-ІІ st. At the same time, complex therapy of SAM and vazonate is superior to the effectiveness of correction of these syndromes due to the implementation of powerful metabolic, antioxidant, antihypoxant, energy-specific properties of Meldonium and may be recommended for the introduction into the practice of internal medicine and gastroenterology for treatment NASH on the background of obesity and CKD I and II stages. The established nephroprotective properties of SAM that are potentiated by Meldonium are probably due to the ability of these drugs to eliminate endothelial dysfunction, improve microcirculation, and prevent the progression of kidney fibrosis. S-adenosylmethionine (ahepta) in a dose of 600 mg sublingually in patients with non-alcoholic steatohepatitis on the background of obesity and chronic kidney disease of the 1st and 2nd st. produces powerful membrane-stabilizing effects on the affected hepatocytes, stably eliminates the clinical manifestations of the disease, the intensity of cytolysis, cholestasis, mesenchymal-inflammatory syndrome, inhibits the progression of hepatic and renal dysfunction (increases the albumin-synthesizing function of the liver, the velocity of glomerular filtration) by optimizing the control of fibrosis of the liver and kidneys. Complex therapy with S-adenosylmethionine (ahape) and Meldonium (500 mg /day)(vasonate) is superior to the correction of these syndromes NASH and CKD, since the vasonate potentially potentiates the action of S-adenosylmethionine in acute and distant observation periods.