In silico study of the mechanisms of hypoxia and contractile dysfunction during ischemia and reperfusion of hiPSC cardiomyocytes.

Interconnected mechanisms of ischemia and reperfusion (IR) has increased the interest in IR in vitro experiments using human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs). We developed a whole-cell computational model of hiPSC-CMs including the electromechanics, a metabolite-sensitive sarcoplasmic reticulum Ca2+-ATPase (SERCA) and an oxygen dynamics formulation to investigate IR mechanisms. Moreover, we simulated the effect and action mechanism of levosimendan, which recently showed promising anti-arrhythmic effects in hiPSC-CMs in hypoxia. The model was validated using hiPSC-CM and in vitro animal data. The role of SERCA in causing relaxation dysfunction in IR was anticipated to be comparable to its function in sepsis-induced heart failure. Drug simulations showed that levosimendan counteracts the relaxation dysfunction by utilizing a particular Ca2+-sensitizing mechanism involving Ca2+-bound troponin C and Ca2+ flux to the myofilament, rather than inhibiting SERCA phosphorylation. The model demonstrates extensive characterization and promise for drug development, making it suitable for evaluating IR therapy strategies based on the changing levels of cardiac metabolites, oxygen and molecular pathways.

Impact of Levosimendan and Its Metabolites on Platelet Activation Mechanisms in Patients during Antiplatelet Therapy-Pilot Study.

Levosimendan is used for the short-term treatment of severe heart failure or other cardiac conditions. The area of existing clinical applications for levosimendan has increased significantly. This study aimed to assess whether levosimendan and its metabolites impact the mechanisms related to platelet activation. In this study, we included patients with coronary artery disease receiving antiplatelet therapy. We analyzed the pharmacodynamic profile using three independent methods to assess platelet activity. The results of the conducted studies indicate a mechanism of levosimendan that affects the function of platelets, causing higher inhibition of platelet receptors and, thus, their aggregation. It is essential to clarify whether levosimendan may affect platelets due to the need to maintain a balance between bleeding and thrombosis in patients treated with levosimendan. This is especially important in the case of perioperative bleeding. This study was conducted in vitro; the research should be continued and carried out in patients to check the complete pharmacokinetic and pharmacodynamic profile.

Acute and chronic effects of levosimendan in the ZSF1 obese rat model of heart failure with preserved ejection fraction.

Heart failure with preserved ejection fraction (HFpEF) is a syndrome characterized by impaired cardiovascular reserve in which therapeutic options are scarce. Our aim was to evaluate the inodilator levosimendan in the ZSF1 obese rat model of HFpEF. Twenty-week-old male Wistar-Kyoto (WKY), ZSF1 lean (ZSF1 Ln) and ZSF1 obese rats chronically treated for 6-weeks with either levosimendan (1 mg/kg/day, ZSF1 Ob + Levo) or vehicle (ZSF1 Ob + Veh) underwent peak-effort testing, pressure-volume (PV) haemodynamic evaluation and echocardiography (n = 7 each). Samples were collected for histology and western blotting. In obese rats, skinned and intact left ventricular (LV) cardiomyocytes underwent in vitro functional evaluation. Seven additional ZSF1 obese rats underwent PV evaluation to assess acute levosimendan effects (10 µg/kg + 0.1 µg/kg/min). ZSF1 Ob + Veh presented all hallmarks of HFpEF, namely effort intolerance, elevated end-diastolic pressures and reduced diastolic compliance as well as increased LV mass and left atrial area, cardiomyocyte hypertrophy and increased interstitial fibrosis. Levosimendan decreased systemic arterial pressures, raised cardiac index, and enhanced LV relaxation and diastolic compliance in both acute and chronic experiments. ZSF1 Ob + Levo showed pronounced attenuation of hypertrophy and interstitial fibrosis alongside increased effort tolerance (endured workload raised 38 %) and maximum O2 consumption. Skinned cardiomyocytes from ZSF 1 Ob + Levo showed a downward shift in sarcomere length-passive tension relationship and intact cardiomyocytes showed decreased diastolic Ca2+ levels and enhanced Ca2+ sensitivity. On molecular grounds, levosimendan enhanced phosphorylation of phospholamban and mammalian target of rapamycin. The observed effects encourage future clinical trials with levosimendan in a broad population of HFpEF patients.

Use of levosimendan in hemodynamic management of heart failure in two neonates with intracranial arteriovenous shunts: a case series.

BACKGROUND: The hemodynamic status of newborns with intracranial arteriovenous shunts (AVSs) may be extremely complex. Mini-invasive hemodynamic monitoring through innovative techniques such as Near-Infrared Spectroscopy (NIRS) and Pressure Recording Analytical Method (PRAM) may help in understanding hemodynamics in newborns with AVSs. Levosimendan is a calcium sensitizer and inodilator, and it is known to improve ventricular function, but its use in newborns is limited. In our cases, we evaluated the effect of levosimendan on hemodynamics through NIRS and PRAM. CASE PRESENTATION: Herein, we report the cases of two neonates with intracranial arteriovenous shunts, in whom we used levosimendan to manage cardiac failure refractory to conventional treatment. Levosimendan was used at a dosage of 0.1 mcg/kg/min for 72 h. Combined use of NIRS and PRAM helped in real-time monitoring of hemodynamic effects; in particular, levosimendan determined significant improvement in myocardium contractility as well as a reduction of heart rate. CONCLUSION: In two neonatal cases of AVSs, levosimendan led to an overall hemodynamic stabilization, documented by the combination of NIRS and PRAM. Our results suggest introducing levosimendan as a second-line treatment in cases of severe cardiac dysfunction due to AVSs without improvement using standard treatment strategies. Future prospective and larger studies are highly warranted.

Hemodynamic failure and graft dysfunction after lung transplant: A possible clinical continuum with immediate and long-term consequences.

INTRODUCTION: The postoperative hemodynamic management after lung transplant (LUTX) is guided by limited evidence. We aimed to describe and evaluate risk factors and outcomes of postoperative vasoactive support of LUTX recipients. METHODS: In a single-center retrospective analysis of consecutive adult LUTX, two cohorts were identified: (1) patients needing prolonged vasoactive support (>12 h from ICU admission) (VASO+); (2) or not (VASO-). Postoperative hemodynamic characteristics were thoroughly analyzed. Risk factors and outcomes of VASO+ versus VASO- cohorts were assessed by multivariate logistic regression and propensity score matching. RESULTS: One hundred and thirty-eight patients were included (86 (62%) VASO+ versus 52 (38%) VASO-). Vasopressors (epinephrine, norepinephrine, dopamine) were used in the first postoperative days (vasoactive inotropic score at 12 h: 6 [4-12]), while inodilators (dobutamine, levosimendan) later. Length of vasoactive support was 3 [2-4] days. Independent predictors of vasoactive use were: LUTX indication different from cystic fibrosis (p = .003), higher Oto score (p = .020), longer cold ischemia time (p = .031), but not preoperative cardiac catheterization. VASO+ patients showed concomitant hemodynamic and graft impairment, with longer mechanical ventilation (p = .010), higher primary graft dysfunction (PGD) grade at 72 h (PGD grade > 0 65% vs. 31%, p = .004, OR 4.2 [1.54-11.2]), longer ICU (p < .001) and hospital stay (p = .013). Levosimendan as a second-line inodilator appeared safe. CONCLUSIONS: Vasoactive support is frequently necessary after LUTX, especially in recipients of grafts of lesser quality. Postoperative hemodynamic dysfunction requiring vasopressor support and graft dysfunction may represent a clinical continuum with immediate and long-term consequences. Further studies may elucidate if this represents a possible treatable condition.

Levosimendan inhibits disulfide tau oligomerization and ameliorates tau pathology in TauP301L-BiFC mice.

Tau oligomers play critical roles in tau pathology and are responsible for neuronal cell death and transmitting the disease in the brain. Accordingly, preventing tau oligomerization has become an important therapeutic strategy to treat tauopathies, including Alzheimer's disease. However, progress has been slow because detecting tau oligomers in the cellular context is difficult. Working toward tau-targeted drug discovery, our group has developed a tau-BiFC platform to monitor and quantify tau oligomerization. By using the tau-BiFC platform, we screened libraries with FDA-approved and passed phase I drugs and identified levosimendan as a potent anti-tau agent that inhibits tau oligomerization. 14C-isotope labeling of levosimendan revealed that levosimendan covalently bound to tau cysteines, directly inhibiting disulfide-linked tau oligomerization. In addition, levosimendan disassembles tau oligomers into monomers, rescuing neurons from aggregation states. In comparison, the well-known anti-tau agents methylene blue and LMTM failed to protect neurons from tau-mediated toxicity, generating high-molecular-weight tau oligomers. Levosimendan displayed robust potency against tau oligomerization and rescued cognitive declines induced by tauopathy in the TauP301L-BiFC mouse model. Our data present the potential of levosimendan as a disease-modifying drug for tauopathies.

Omecamtiv mecarbil augments cardiomyocyte contractile activity both at resting and systolic Ca2+ levels.

AIMS: Heart failure with reduced ejection fraction (HFrEF) is a disease with high mortality and morbidity. Recent positive inotropic drug developments focused on cardiac myofilaments, that is, direct activators of the myosin molecule and Ca2+ sensitizers for patients with advanced HFrEF. Omecamtiv mecarbil (OM) is the first direct myosin activator with promising results in clinical studies. Here, we aimed to elucidate the cellular mechanisms of the positive inotropic effect of OM in a comparative in vitro investigation where Ca2+ -sensitizing positive inotropic agents with distinct mechanisms of action [EMD 53998 (EMD), which also docks on the myosin molecule, and levosimendan (Levo), which binds to troponin C] were included. METHODS: Enzymatically isolated canine cardiomyocytes with intact cell membranes were loaded with Fura-2AM, a Ca2+ -sensitive, ratiometric, fluorescent dye. Changes in sarcomere length (SL) and intracellular Ca2+ concentration were recorded in parallel at room temperature, whereas cardiomyocyte contractions were evoked by field stimulation at 0.1 Hz in the presence of different OM, EMD, or Levo concentrations. RESULTS: SL was reduced by about 23% or 9% in the presence of 1 µM OM or 1 µM EMD in the absence of electrical stimulation, whereas 1 µM Levo had no effect on resting SL. Fractional sarcomere shortening was increased by 1 µM EMD or 1 µM Levo to about 152%, but only to about 128% in the presence of 0.03 µM OM. At higher OM concentrations, no significant increase in fractional sarcomere shortening could be recorded. Contraction durations largely increased, whereas the kinetics of contractions and relaxations decreased with increasing OM concentrations. One-micromole EMD or 1 µM Levo had no effects on contraction durations. One-micromole Levo, but not 1 µM EMD, accelerated the kinetics of cardiomyocyte contractions and relaxations. Ca2+ transient amplitudes were unaffected by all treatments. CONCLUSIONS: Our data revealed major distinctions between the cellular effects of myofilament targeted agents (OM, EMD, or Levo) depending on their target proteins and binding sites, although they were compatible with the involvement of Ca2+ -sensitizing mechanisms for all three drugs. Significant part of the cardiotonic effect of OM relates to the prolongation of systolic contraction in combination with its Ca2+ -sensitizing effect.

Levosimendan in outpatients with advanced heart failure: Single-center experience of 200 intermittent perfusions.

INTRODUCTION: Patients with advanced heart failure (HF) have high morbidity and mortality, with only a small proportion being eligible for advanced therapies. Intermittent outpatient levosimendan infusion has been shown to provide symptomatic relief and reduce the rate of HF events. Our aim was to assess the safety and efficacy of outpatient levosimendan administration in an advanced HF population. METHODS: This is a report of a single-center experience of consecutive advanced HF patients referred for intermittent intravenous outpatient administration of levosimendan, between January 2018 and March 2021. Baseline and follow-up evaluation included clinical assessment, laboratory tests, transthoracic echocardiography and cardiopulmonary exercise testing. Baseline and clinical follow-up data were compared using the Wilcoxon signed-rank test. RESULTS: A total of 24 patients (60.8 years, 83% male, mean left ventricular ejection fraction [LVEF] 24%), with a median of 1.5 HF hospitalizations in the previous six months, were referred for outpatient levosimendan pulses, the majority as a bridge to transplantation or due to clinical deterioration. At six-month follow-up there was a significant reduction in HF hospitalizations to 0.4±0.7 (p<0.001). NYHA class IV (52.2% to 12.5%, p=0.025) and NT-proBNP (8812.5 to 3807.4 pg/ml, p=0.038) were also significantly reduced. Exercise capacity was significantly improved, including peak oxygen uptake (p=0.043) and VE/VCO2 slope (p=0.040). LVEF improved from 24.0% to 29.7% (p=0.008). No serious adverse events were reported. CONCLUSION: Repeated levosimendan administration in advanced HF patients is a safe procedure and was associated with a reduction in HF hospitalizations, functional and LVEF improvement, and reduction in NT-proBNP levels during follow-up.

Levosimendan: mechanistic insight and its diverse future aspects in cardiac care.

Inotropic agents are generally recommended to use in patients with acute decompensated heart failure (HF) with reduced ejection fraction (HFrEF) concurrent to end-organ dysfunction. However, due to certain pharmacological limitations like developing life threatening arrhythmia and tolerance, cannot be employed as much as needed. Meanwhile, Calcium ion (Ca2+) sensitisers exhibits their inotropic action by increasing the sensitivity of the cardiomyocyte to intracellular Ca2+ ion and have been reported as emerging therapeutic alternative in HF cases. Levosimendan (LEVO) is an inodilator and with its unique pharmacology justifying its use in a wide range of cardiac alterations in HF particularly in undergoing cardiac surgery. It is also reported to be better than classical inotropes in maintaining cardiac mechanical efficacy and reducing congestion in acute HF with hypotension. This review paper was designed to compile various evidence about basic pharmacology and potential clinical aspects of LEVO in cardiac surgery and other HF associated alterations. This will benefit directly to the researcher in initiating research and to fill the gaps in the area of thrust.

Levosimendan increases the phosphorylation state of phospholamban in the isolated human atrium.

Levosimendan (up to 10 µM) given alone failed to increase force of contraction in isolated electrically stimulated (1 Hz) left atrial (LA) preparations from wild-type mice. Only in the additional presence of 0.1 µM rolipram, an inhibitor of the activity of phosphodiesterase IV, levosimendan increased force of contraction in LA and increased the phosphorylation state of phospholamban at amino acid serine 16. Levosimendan alone increased the beating rate in isolated spontaneously beating right atrial preparations from mice and this effect was potentiated by rolipram. The positive inotropic and the positive chronotropic effects of levosimendan in mouse atrial preparations were attenuated by 10 µM propranolol. Finally, we studied the contractile effects of levosimendan in isolated electrically stimulated (1 Hz) right atrial preparations from the human atrium (HAP), obtained during cardiac surgery. We detected concentration-dependent positive inotropic effects of levosimendan alone that reached plateau at 1 µM levosimendan in HAP (n = 11). Levosimendan shortened time of tension relaxation in HAP. Cilostamide (1 µM), an inhibitor of phosphodiesterase III, or propranolol (10 µM) blocked the positive inotropic effect of levosimendan in HAP. Levosimendan (1 µM) alone increased in HAP the phosphorylation state of phospholamban. In conclusion, we present evidence that levosimendan acts via phosphodiesterase III inhibition in the human atrium leading to phospholamban phosphorylation and thus explaining the positive inotropic effects of levosimendan in HAP.

A New Approach in the Treatment of Traumatic Brain Injury: The Effects of Levosimendan on Necrosis, Apoptosis, and Oxidative Stress.

OBJECTIVE: Traumatic brain injury (TBI) is an essential and common health problem worldwide. Levosimendan is an inotropic and vasodilator drug used to treat heart failure. Moreover, it exerts pleiotropic effects and, thus, protective effects on many organs. The present study aimed to investigate the effect of levosimendan on necrosis, apoptosis, and reactive oxygen species in rats with TBI. METHODS: The study included 28 female Wistar-Albino rats weighing 200-250 g. The rats were divided into 4 groups with 7 rats each as follows: Group 1: No trauma group (Control), Group 2: Traumatized, untreated group (T), Group 3: Levosimendan was administered at a dose of 12 µg/kg intraperitoneally 1 hour after the trauma (L1), Group 4: Levosimendan was administered at a dose of 12 µg/kg intraperitoneally 2 hours after the concussion (L2). After the experiment, the rats were decapitated, and the brain tissue was removed. Necrosis was assessed with Cresyl violet staining, apoptosis was assessed with immunohistochemical analysis, superoxide dismutase and catalase levels were measured with the spectrophotometric method, and malondialdehyde (MDA) levels were assessed by High-Performance Liquid Chromatography. RESULTS: The number of necrotic cells in the L1 and L2 groups was significantly lower than in the K and T groups (P = 0.015 and P = 0.03, respectively). Although the active caspase-3 level was signified considerably in the T, L1, and L2 groups compared to the K group, no significant difference was found among these 3 groups (P > 0.05). The results of superoxide dismutase levels were similar to those of active caspase-3. catalase level was significantly higher in the K group than in the T and L2 groups (P = 0.045). Malondialdehyde activity was considerably higher in the L1 and L2 groups compared to the K group (P = 0.023). CONCLUSIONS: Our results indicated that levosimendan may exert a neuroprotective effect by reducing necrosis in TBI and that levosimendan does not affect apoptosis and antioxidant levels in TBI. Comprehensive studies are needed to elucidate the effect of levosimendan on TBI fully.

Cardiac Ischemia On-a-Chip: Antiarrhythmic Effect of Levosimendan on Ischemic Human-Induced Pluripotent Stem Cell-Derived Cardiomyocytes.

Ischemic heart disease (IHD) is one of the leading causes of mortality worldwide. Preserving functionality and preventing arrhythmias of the heart are key principles in the management of patients with IHD. Levosimendan, a unique calcium (Ca2+) enhancer with inotropic activity, has been introduced into clinical usage for heart failure treatment. Human-induced pluripotent cell-derived cardiomyocytes (hiPSC-CMs) offer an opportunity to better understand the pathophysiological mechanisms of the disease as well as to serve as a platform for drug screening. Here, we developed an in vitro IHD model using hiPSC-CMs in hypoxic conditions and defined the effects of the subsequent hypoxic stress on CMs functionality. Furthermore, the effect of levosimendan on hiPSC-CMs functionality was evaluated during and after hypoxic stress. The morphology, contractile, Ca2+-handling, and gene expression properties of hiPSC-CMs were investigated in response to hypoxia. Hypoxia resulted in significant cardiac arrhythmia and decreased Ca2+ transient amplitude. In addition, disorganization of sarcomere structure was observed after hypoxia induction. Interestingly, levosimendan presented significant antiarrhythmic properties, as the arrhythmia was abolished or markedly reduced with levosimendan treatment either during or after the hypoxic stress. Moreover, levosimendan presented significant protection from the sarcomere alterations induced by hypoxia. In conclusion, this chip model appears to be a suitable preclinical representation of IHD. With this hypoxia platform, detailed knowledge of the disease pathophysiology can be obtained. The antiarrhythmic effect of levosimendan was clearly observed, suggesting a possible new clinical use for the drug.

Levosimendan Postconditioning Attenuates Cardiomyocyte Apoptosis after Myocardial Infarction.

BACKGROUND: Levosimendan preconditioning has been shown to attenuate myocardial apoptosis in animal models. However, protective effects of levosimendan postconditioning against myocardial apoptosis following myocardial infarction (MI) have not been evaluated. Therefore, we investigated the effects of levosimendan postconditioning on myocardial apoptosis in MI rat models. METHODS: In an anoxia/reoxygenation (A/R) model, H9c2 cells were pretreated with or without levosimendan postconditioning after which their apoptosis rates were assessed by flow cytometry, RT-qPCR, and western blot analyses. Then, postconditioning was performed with or without levosimendan in MI rat models. Myocardiocyte apoptosis was evaluated by echocardiography, TTC staining, TUNEL staining, immunohistochemical staining, RT-qPCR, and western blot analysis. RESULTS: Levosimendan postconditioning inhibited H9c2 cell apoptosis in A/R models by elevating Bcl-2 while suppressing Caspase-3 and Bax at both mRNA and protein levels. Moreover, it improved cardiac functions and reduced the left ventricle infarction area in MI rat models. Compared to the MI control group, cardiomyocyte apoptosis rates in the levosimendan postconditioning group were low. The reduced cardiomyocyte apoptosis rates were associated with downregulation of Bax and Caspase-3 as well as with upregulation of Bcl-2 at mRNA and protein levels. CONCLUSIONS: Levosimendan postconditioning of MI rat models protected against cardiomyocyte apoptosis, implying that it is a potential strategy for preventing cardiomyocyte apoptosis in the treatment of cardiac dysfunction following MI.

The Adenylate Cyclase Activator Forskolin Potentiates the Positive Inotropic Effect of the Phosphodiesterase Inhibitor Milrinone But Not of the Calcium Sensitizer Levosimendan nor of Its Hemodynamically Active Metabolites: An Apparent Conundrum.

ABSTRACT: OR-1855 and OR-1896 are 2 hemodynamically active metabolites of the inodilator levosimendan, with calcium sensitizing activity, but their mechanism of action is still not fully understood. It has been previously reported that the positive inotropic effect of levosimendan is not potentiated by the adenylate cyclase activator forskolin, whereas forskolin does potentiate the effects of the phosphodiesterase (PDE) inhibitor milrinone. To ascertain whether the active metabolites follow the same pattern of levosimendan, the positive inotropic effects of OR- 1855 and OR-1896 were studied in guinea-pig-isolated papillary muscle in the presence and absence of forskolin. OR-1855 and OR-1896 were also tested as inhibitors of PDE-III and PDE-IV. Our results show that 0.1 µM forskolin did not potentiate the positive inotropic effect of OR-1855 or OR-1896, as in the case of the parent compound levosimendan. As in previous studies, the positive inotropic effect of milrinone was markedly potentiated in the presence of forskolin. From these data, we propose an explanation for the divergent behavior of the calcium sensitizing drugs and PDE inhibitors.

Combined levosimendan and Sacubitril/Valsartan markedly protected the heart and kidney against cardiorenal syndrome in rat.

BACKGROUND: Cardiorenal syndrome (CRS) remains the leading cause of death in hospitalized patients for all disease entities. Sacubitril/Valsartan (Sac/Val) therapy has been proved to improve prognostic outcome in patients with heart failure or chronic kidney disease. This study tested the hypothesis that combined levosimendan and Sac/Val was superior to just one therapy on protecting the heart and kidney against simultaneous heart and kidney ischemia (I) (for 50-min)-reperfusion (R) (for 7-days) (i.e., double IR) injury (defined as CRS). METHODS AND RESULTS: Adult-male Spraque-Dawley rats (n = 40) were equally categorized into group 1 (sham-operated control), group 2 (double IR), group 3 [double IR+levosimendan (10 mg/kg by intra-peritoneum administration at 30 min/followed by days 1-5 once daily after IR procedure)], group 4 [double IR+Sac/Val (10 mg/kg, orally at 30 min/followed by days 1-5 twice daily after IR procedure)], and group 5 (double IR+Sac/Val+levosimendan). By day 7 after double-IR, the left-ventricular-ejection fraction (LVEF)/left-ventricular-fraction-shortening (LVFS) were highest in group 1, lowest in group 2 and significantly higher in group 5 than in groups 3/4, but they showed no difference between groups 3/4, whereas the circulatory heart-failure (brain-natriuretic peptide)/proinflammatory (suppression of tumorigenicity-2) biomarkers, blood-urea-nitrogen/creatinine and ratio of urine protein to creatinine (all p < 0.0001) exhibited an opposite pattern of LVEF among the groups. The protein expressions of inflammatory (tumor necrosis factor-α/interleukin-1ß/matrix metalloproteinase-9)/oxidative-stress (NOX-1/NOX-2/NOX-4)/apoptotic (mitochondrial-Bax/caspase-3/poly-(ADP-ribose)-polymerase)/fibrotic (Smad3/transforming growth factor-ß)/mitochondrial-damaged (cytosolic-cytochrome-C)/myocardial-hypertrophic (ß-MHC) biomarkers in LV myocardium exhibited an opposite pattern of LVEF among the groups (all p < 0.0001). The cellular expressions of inflammatory (CD68)/DNA-damaged (γ-H2AX) biomarkers and infarct/fibrotic areas in LV myocardium and kidney displayed an opposite pattern of LVEF among the groups (all p < 0.0001). CONCLUSION: Combined levosimendan and Sac/Val was superior to merely one therapy on protecting the heart and kidney as well as preserving their functions against double IR injury.

Levosimendan as a therapeutic strategy to prevent neuroinflammation after aneurysmal subarachnoid hemorrhage?

BACKGROUND: Poor patient outcomes after aneurysmal subarachnoid hemorrhage (SAH) occur due to a multifactorial process, mainly involving cerebral inflammation (CI), delayed cerebral vasospasm (DCVS), and delayed cerebral ischemia, followed by neurodegeneration. CI is mainly triggered by enhanced synthesis of serotonin (5-HT), prostaglandin F2alpha (PGF2a), and cytokines such as interleukins. Levosimendan (LV), a calcium-channel sensitizer, has already displayed anti-inflammatory effects in patients with severe heart failure. Therefore, we wanted to elucidate its potential anti-inflammatory role on the cerebral vasculature after SAH. METHODS: Experimental SAH was induced by using an experimental double-hemorrhage model. Sprague Dawley rats were harvested on day 3 and day 5 after the ictus. The basilar artery was used for isometric investigations of the muscular media tone. Vessel segments were either preincubated with LV or without, with precontraction performed with 5-HT or PGF2a followed by application of acetylcholine (ACh) or LV. RESULTS: After preincubation with LV 10-4 M and 5-HT precontraction, ACh triggered a strong vasorelaxation in sham segments (LV 10-4 M, Emax 65%; LV 10-5 M, Emax 48%; no LV, Emax 53%). Interestingly, SAH D3 (LV 10-4, Emax 76%) and D5 (LV 10-4, Emax 79%) segments showed greater vasorelaxation compared with sham. An LV series after PGF2a precontraction showed significantly enhanced relaxation in the sham (P=0.004) and SAH groups (P=0.0008) compared with solvent control vessels. CONCLUSIONS: LV application after SAH seems to beneficially influence DCVS by antagonizing 5-HT- and PGF2a-triggered vasoconstriction. Considering this spasmolytic effect, LV might have a role in the treatment of SAH, additionally in selected patients suffering takotsubo cardiomyopathy.

The effect of levosimendan on right ventricular function in patients with heart dysfunction: a systematic review and meta-analysis.

Levosimendan exerts positive inotropic and vasodilatory effects. Currently, its effects on right heart function remain uncertain. This systematic review and meta-analysis is intended to illustrate the impacts of levosimendan on systolic function of the right heart in patients with heart dysfunction. We systematically searched electronic databases (PubMed, the Cochrane Library, Embase and Web of Science) up to November 30, 2020, and filtered eligible studies that reported the impacts of levosimendan on right heart function. Of these, only studies whose patients suffered from heart dysfunction or pulmonary hypertension were included. Additionally, patients were divided into two groups (given levosimendan or not) in the initial research. Then, RevMan5.3 was used to conduct further analysis. A total of 8 studies comprising 390 patients were included. The results showed that after 24 h of levosimendan, patients' right ventricular fractional area change [3.17, 95% CI (2.03, 4.32), P < 0.00001], tricuspid annular plane systolic excursion [1.26, 95% CI (0.35, 2.16), P = 0.007] and tricuspid annular peak systolic velocity [0.86, 95% CI (0.41, 1.32), P = 0.0002] were significantly increased compared to the control group. And there is an increasing trend of cardiac output in levosimendan group [1.06, 95% CI (- 0.16, 2.29), P = 0.09 ] .Furthermore, patients' systolic pulmonary arterial pressure [- 5.57, 95% CI (- 7.60, - 3.54), P < 0.00001] and mean pulmonary arterial pressure [- 1.01, 95% CI (- 1.64, - 0.37), P = 0.002] were both significantly decreased, whereas changes in pulmonary vascular resistance [- 55.88, 95% CI (- 206.57, 94.82), P = 0.47] were not significant. Our study shows that in patients with heart dysfunction, levosimendan improves systolic function of the right heart and decreases the pressure of the pulmonary artery.

Does the cardiovascular drug levosimendan prevent iodinated contrast medium nephrotoxicity with glycerol aggravation in rats?

BACKGROUND: We investigated whether levosimendan prevents contrast medium nephrotoxicity with glycerol aggravation in rats. METHODS: Forty-eight Wistar albino rats were assigned to eight groups (n = 6 × 8). No medication was administered to group I (controls); glycerol (intramuscular injection of 25% glycerol, 10 mL/kg) group II; intravenous iohexol 10 mL/kg to group III; glycerol and iohexol to group IV; iohexol and intraperitoneal levosimendan 0.25 mg/kg to group V; glycerol, iohexol, and levosimendan 0.25 mg/kg to group VI; iohexol and levosimendan 0.5 mg/kg to group VII; and glycerol, iohexol, and levosimendan 0.5 mg/kg to group VIII. One-day water withdrawal and glycerol injection prompted renal damage; iohexol encouraged nephrotoxicity; levosimendan was administered 30 min after glycerol injection and continued on days 2, 3, and 4. The experiment was completed on day 5. Serum blood urea nitrogen (BUN) and creatinine levels, superoxide dismutase (SOD) activity, glutathione (GSH), malondialdehyde (MDA) levels, tumour necrosis factor-α (TNF-α), nuclear factor kappa ß (NFK-ß), interleukin 6 (IL-6), and histopathological marks were assessed. One-way analysis of variance and Duncan's multiple comparison tests were used. RESULTS: Levosimendan changed serum BUN (p = 0.012) and creatinine (p = 0.018), SOD (p = 0.026), GSH (p = 0.012), and MDA (p = 0.011). Levosimendan significantly downregulated TNF-α (p = 0.022), NFK-ß (p = 0.008), and IL-6 (p = 0.033). Histopathological marks of hyaline and haemorrhagic cast were improved in levosimendan-injected groups. CONCLUSION: Levosimendan showed nephroprotective properties due to its vasodilator, oxidative distress decreasing and inflammatory cytokine preventing belongings.