0000000000016227

AUTHOR

Panagiotis Efentakis

Tubulin-folding cofactor E deficiency is associated with vascular dysfunction and endoplasmatic reticulum stress of vascular smooth muscle cells

Abstract Introduction Endothelial function assessed via flow mediated dilatation (FMD) has shown to predict risk in individuals with established cardiovascular diseases, whereas its predictive value is uncertain in the setting primary prevention. Purpose The aim of the current work was to discover and evaluate novel mediators of vascular dysfunction in the general population and in conditional knock-out transgenic animal models. Methods In order to identify novel targets that were negatively correlated with FMD and investigate their contribution in vascular function, a Genome Wide Association Study (GWAS) of 5,000 participants was performed and subsequently immune cell-, endothelial- and va…

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Molecular mechanisms of carfilzomib-induced cardiotoxicity in mice and the emerging cardioprotective role of metformin

AbstractCarfilzomib (Cfz), an irreversible proteasome inhibitor licensed for relapsed/refractory myeloma, is associated with cardiotoxicity in humans. We sought to establish the optimal protocol of Cfz-induced cardiac dysfunction, to investigate the underlying molecular-signaling and, based on the findings, to evaluate the cardioprotective potency of metformin (Met). Mice were randomized into protocols 1 and 2 (control and Cfz for 1 and 2 consecutive days, respectively); protocols 3 and 4 (control and alternate doses of Cfz for 6 and 14 days, respectively); protocols 5A and 5B (control and Cfz, intermittent doses on days 0, 1 [5A] and 0, 1, 7, and 8 [5B] for 13 days); protocols 6A and 6B (p…

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Metformin Restores AMPK Alpha-Mediated Autophagy and Prevents Carfilzomib-Induced Cardiotoxicity In Vivo

Abstract Introduction: Carfilzomib (Cfz) significantly prolongs progression-free survival in relapsed or refractory multiple myeloma patients, as highlighted in the ENDEAVOR trial. However, Cfz has high incidences of cardiotoxicity and heart failure, leading to treatment cessation. Thus, there is an imperative need for preventive therapies. The study aimed to i) establish an in vivo Cfz cardiotoxicity protocol, ii) investigate the molecular mechanism, identify molecular targets and iii) based on initial results, investigate the potential protective effect and mechanism of Metformin (Met). Methods: Male, C57BL/6 mice, were randomized in groups as following: Acute protocol (6 days): Control (…

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P3488Mechanistic insight on the cardioprotective effect of levosimendan against doxorubicin induced cardiomyopathy: Pivotal role of PKA signaling

Abstract Background Levosimendan (LEVO) an inodilator indicated for the treatment of heart failure exerts multifaceted cardioprotective effects. Case-studies indicate protection against doxorubicin (DXR)-induced cardiotoxicity, but this effect remains elusive. We have previously shown that LEVO exerts cardioprotection against DXR-induced cardiomyopathy in a rat in vivo model, in a PKA/PKG-dependent manner. Purpose We sought to elucidate the mechanism of LEVO's induced cardioprotection and clarify the contribution of PKG and PKA pathways converging onto phospholamban (PLN). Methods As previously observed, LEVO at a dose of 24μg/kg protects against DXR cardiotoxicity, with protein kinase B (A…

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Levosimendan prevents doxorubicin-induced cardiotoxicity in time- and dose-dependent manner: implications for inotropy.

Abstract Aims Levosimendan (LEVO) a clinically-used inodilator, exerts multifaceted cardioprotective effects. Case-studies indicate protection against doxorubicin (DXR)-induced cardiotoxicity, but this effect remains obscure. We investigated the effect and mechanism of different regimens of levosimendan on sub-chronic and chronic doxorubicin cardiotoxicity. Methods and results Based on preliminary in vivo experiments, rats serving as a sub-chronic model of doxorubicin-cardiotoxicity and were divided into: Control (N/S-0.9%), DXR (18 mg/kg-cumulative), DXR+LEVO (LEVO, 24 μg/kg-cumulative), and DXR+LEVO (acute) (LEVO, 24 μg/kg-bolus) for 14 days. Protein kinase-B (Akt), endothelial nitric oxi…

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Investigating the Vascular Toxicity Outcomes of the Irreversible Proteasome Inhibitor Carfilzomib

Background: Carfilzomib&rsquo

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Aestivation motifs explain hypertension and muscle mass loss in mice with psoriatic skin barrier defect

Aim Recent evidence suggests that arterial hypertension could be alternatively explained as a physiological adaptation response to water shortage, termed aestivation, which relies on complex multi-organ metabolic adjustments to prevent dehydration. Here, we tested the hypothesis that chronic water loss across diseased skin leads to similar adaptive water conservation responses as observed in experimental renal failure or high salt diet. Methods We studied mice with keratinocyte-specific overexpression of IL-17A which develop severe psoriasis-like skin disease. We measured transepidermal water loss and solute and water excretion in the urine. We quantified glomerular filtration rate (GFR) by…

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Synergistic Effect of Carfilzomib and Metformin in Vascular Plasticity; The Emerging Role of Autophagy

Introduction: Carfilzomib (Cfz) correlates with a risk of reversible cardiotoxicity in 5-10% of multiple myeloma (MM) patients. We have recently shown that metformin (Met) has a prophylactic role against the Cfz-induced cardiotoxicity in vivo, through activation of AMPKα signaling (Blood 2019;133:710-23). However, the impact of Cfz on vascular function is obscure. Therefore, we sought to investigate: i) the acute, ii) the sub-chronic effect of Cfz on the vascular reactivity, iii) the effect of metformin co-administration on the vascular phenotype and iv) the impact of Cfz and Met co-administration on aged Human Aortic Smooth Muscle Cells (HAoSMCs). Methods: Forty male C57Bl/6 mice were assi…

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Investigating and re-evaluating the role of glycogen synthase kinase 3 beta kinase as a molecular target for cardioprotection by using novel pharmacological inhibitors

Aims Glycogen synthase kinase 3 beta (GSK3β) link with the mitochondrial Permeability Transition Pore (mPTP) in cardioprotection is debated. We investigated the role of GSK3β in ischaemia (I)/reperfusion (R) injury using pharmacological tools. Methods and results Infarct size using the GSK3β inhibitor BIO (6-bromoindirubin-3'-oxime) and several novel analogues (MLS2776-MLS2779) was determined in anaesthetized rabbits and mice. In myocardial tissue GSK3β inhibition and the specificity of the compounds was tested. The mechanism of protection focused on autophagy-related proteins. GSK3β localization was determined in subsarcolemmal (SSM) and interfibrillar mitochondria (IFM) isolated from Lang…

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