Implications and hidden toxicity of cardiometabolic syndrome and early-stage heart failure in carfilzomib-induced cardiotoxicity.

BACKGROUND AND PURPOSE: Cancer therapy-related cardiovascular adverse events (CAEs) in presence of comorbidities, are in the spotlight of the cardio-oncology guidelines. Carfilzomib (Cfz), indicated for relapsed/refractory multiple myeloma (MM), presents with serious CAEs. MM is often accompanied with co-existing comorbidities. However, Cfz use in MM patients with cardiometabolic syndrome (CMS) or in heart failure with reduced ejection fraction (HFrEF), is questionable. EXPERIMENTAL APPROACH: ApoE-/- and C57BL6/J male mice received 14 weeks Western Diet (WD) (CMS models). C57BL6/J male mice underwent permanent LAD ligation for 14 days (early-stage HFrEF model). CMS- and HFrEF-burdened mice received Cfz for two consecutive or six alternate days. Daily metformin and atorvastatin administrations were performed additionally to Cfz, as prophylactic interventions. Mice underwent echocardiography, while proteasome activity, biochemical and molecular analyses were conducted. KEY RESULTS: CMS did not exacerbate Cfz left ventricular (LV) dysfunction, whereas Cfz led to metabolic complications in both CMS models. Cfz induced autophagy and Ca2+ homeostasis dysregulation, whereas metformin and atorvastatin prevented Cfz-mediated LV dysfunction and molecular deficits in the CMS-burdened myocardium. Early-stage HFrEF led to depressed LV function and increased protein phosphatase 2A (PP2A) activity. Cfz further increased myocardial PP2A activity, inflammation and Ca2+-cycling dysregulation. Metformin co-administration exerted an anti-inflammatory potential on the myocardium without improving LV function. CONCLUSION AND IMPLICATIONS: CMS and HFrEF seem to exacerbate Cfz-induced CAEs, by presenting metabolism-related hidden toxicity and PP2A-related cardiac inflammation, respectively. Metformin retains its prophylactic potential in the presence of CMS, while mitigating inflammation and Ca2+ signalling dysregulation in the HFrEF myocardium.

Is There a Mitochondrial Protection via Remote Ischemic Conditioning in Settings of Anticancer Therapy Cardiotoxicity?

PURPOSE OF REVIEW: To provide an overview of (a) protective effects on mitochondria induced by remote ischemic conditioning (RIC) and (b) mitochondrial damage caused by anticancer therapy. We then discuss the available results of studies on mitochondrial protection via RIC in anticancer therapy-induced cardiotoxicity. RECENT FINDINGS: In three experimental studies in healthy mice and pigs, there was a RIC-mediated protection against anthracycline-induced cardiotoxicity and there was some evidence of improved mitochondrial function with RIC. The RIC-mediated protection was not confirmed in the two available studies in cancer patients. In adult cancer patients, RIC was associated with an adverse outcome. There are no data on mitochondrial function in cancer patients. Studies in tumor-bearing animals are needed to determine whether RIC does not interfere with the anticancer properties of the drugs and whether RIC actually improves mitochondrial function, ultimately resulting in improved cardiac function.

Early microvascular coronary endothelial dysfunction precedes pembrolizumab-induced cardiotoxicity. Preventive role of high dose of atorvastatin.

Immune checkpoint inhibitors (ICIs) exhibit remarkable antitumor activity and immune-related cardiotoxicity of unknown pathomechanism. The aim of the study was to investigate the ICI class-dependent cardiotoxicity in vitro and pembrolizumab's (Pem's) cardiotoxicity in vivo, seeking for translational prevention means. Cytotoxicity was investigated in primary cardiomyocytes and splenocytes, incubated with ipilimumab, Pem and avelumab. Pem's cross-reactivity was assessed by circular dichroism (CD) on biotechnologically produced human and murine PD-1 and in silico. C57BL6/J male mice received IgG4 or Pem for 2 and 5 weeks. Echocardiography, histology, and molecular analyses were performed. Coronary blood flow velocity mapping and cardiac magnetic resonance imaging were conducted at 2 weeks. Human EA.hy926 endothelial cells were incubated with Pem-conditioned media from human mononuclear cells, in presence and absence of statins and viability and molecular signaling were assessed. Atorvastatin (20 mg/kg, daily) was administered in vivo, as prophylaxis. Only Pem exerted immune-related cytotoxicity in vitro. Pem's cross-reactivity with the murine PD-1 was confirmed by CD and docking. In vivo, Pem initiated coronary endothelial and diastolic dysfunction at 2 weeks and systolic dysfunction at 5 weeks. At 2 weeks, Pem induced ICAM-1 and iNOS expression and intracardiac leukocyte infiltration. At 5 weeks, Pem exacerbated endothelial activation and triggered cardiac inflammation. Pem led to immune-related cytotoxicity in EA.hy926 cells, which was prevented by atorvastatin. Atorvastatin mitigated functional deficits, by inhibiting endothelial dysfunction in vivo. We established for the first time an in vivo model of Pem-induced cardiotoxicity. Coronary endothelial dysfunction precedes Pem-induced cardiotoxicity, whereas atorvastatin emerges as a novel prophylactic therapy.

Heart failure pharmacotherapy and cancer: pathways and pre-clinical/clinical evidence.

Heart failure (HF) patients have a significantly higher risk of new-onset cancer and cancer-associated mortality, compared to subjects free of HF. While both the prevention and treatment of new-onset HF in patients with cancer have been investigated extensively, less is known about the prevention and treatment of new-onset cancer in patients with HF, and whether and how guideline-directed medical therapy (GDMT) for HF should be modified when cancer is diagnosed in HF patients. The purpose of this review is to elaborate and discuss the effects of pillar HF pharmacotherapies, as well as digoxin and diuretics on cancer, and to identify areas for further research and novel therapeutic strategies. To this end, in this review, (i) proposed effects and mechanisms of action of guideline-directed HF drugs on cancer derived from pre-clinical data will be described, (ii) the evidence from both observational studies and randomized controlled trials on the effects of guideline-directed medical therapy on cancer incidence and cancer-related outcomes, as synthetized by meta-analyses will be reviewed, and (iii) considerations for future pre-clinical and clinical investigations will be provided.

Monoclonal Gammopathy of Undetermined Cardiovascular Significance; Current Evidence and Novel Insights.

Monoclonal gammopathy of undetermined significance (MGUS) is a premalignant condition characterized by the presence of low levels of a monoclonal protein in the serum and a low percentage of clonal plasma cells in the bone marrow. MGUS may progress to multiple myeloma or other plasma cell disorders at a rate of 1% annually. However, MGUS may also have adverse effects on the cardiovascular system independent of its malignant potential. Emerging data have shown that MGUS is associated with cardiovascular disease. The mechanisms underlying this association are not fully understood but may involve genetic abnormalities, vascular calcification, cryoglobulinemia, cold agglutinin disease, autoantibodies and the direct or indirect effects of the monoclonal protein on the vascular endothelium. Herein, we review current evidence in this field and we suggest that patients with MGUS may benefit from regular cardiovascular risk assessment to prevent severe cardiovascular complications, in parallel with close hematological follow-up to monitor potential disease progression.

Hydrolytic Activity of Mitochondrial F1FO-ATP Synthase as a Target for Myocardial Ischemia-Reperfusion Injury: Discovery and In Vitro and In Vivo Evaluation of Novel Inhibitors.

F1FO-ATP synthase is the mitochondrial complex responsible for ATP production. During myocardial ischemia, it reverses its activity, hydrolyzing ATP and leading to energetic deficit and cardiac injury. We aimed to discover novel inhibitors of ATP hydrolysis, accessing the druggability of the target within ischemia(I)/reperfusion(R) injury. New molecular scaffolds were revealed using ligand-based virtual screening methods. Fifty-five compounds were tested on isolated murine heart mitochondria and H9c2 cells for their inhibitory activity. A pyrazolo[3,4-c]pyridine hit structure was identified and optimized in a hit-to-lead process synthesizing nine novel derivatives. Three derivatives significantly inhibited ATP hydrolysis in vitro, while in vivo, they reduced myocardial infarct size (IS). The novel compound 31 was the most effective in reducing IS, validating that inhibition of F1FO-ATP hydrolytic activity can serve as a target for cardioprotection during ischemia. Further examination of signaling pathways revealed that the cardioprotection mechanism is related to the increased ATP content in the ischemic myocardium and increased phosphorylation of PKA and phospholamban, leading to the reduction of apoptosis.

The Short-Term Effect of Olive Oil Extract Enriched with Hydroxytyrosol on Cardiovascular Function.

Olive is rich in polyphenols such as hydroxytyrosol (HT) that have antioxidative and anti-inflammatory effects. In this study, we examined the short-term effects of olive oil extract (OE) enriched with HT on left atrial function, left ventricular (LV) function, and arterial elastic properties in patients with chronic coronary artery disease (CAD). Sixty-one patients with chronic CAD were enrolled. This randomized study had a two-period, two-sequence crossover (AB/BA) design. Group AB (n = 32) initially received OE capsules (500 mg) enriched with HT (5 mg) (two capsules/day) for 30 days, and after a wash out of 48 h, placebo for another 30 days. The opposite occurred in Group BA (n = 29). Exclusion criteria included age >70 years, diabetes, anemia, hypertension, liver and thyroid disease, malignancy, autoimmune disease, kidney disease, use of corticosteroids, weight loss, excessive exercise dietary intervention, and use of antioxidant vitamins. Patients underwent echocardiography/Doppler and applanation tonometry applied to radial artery at the beginning and end of the study. No significant change regarding Vmax, Vp, Vmin, E wave, A wave, deceleration time, LV ejection fraction, central aortic systolic and pulse pressure, and augmentation index. However, a trend toward improvement of E/e' (P = .062) and pulse wave velocity (P = .091) was observed. Use of OE enriched with HT for a limited time period was associated with a trend toward improvement of LV diastolic function and aortic elastic properties in chronic CAD patients. Studies of longer duration are needed to delineate the effect of this promising agent on cardiovascular function and outcomes in chronic CAD.

Health position paper and redox perspectives on reactive oxygen species as signals and targets of cardioprotection.

The present review summarizes the beneficial and detrimental roles of reactive oxygen species in myocardial ischemia/reperfusion injury and cardioprotection. In the first part, the continued need for cardioprotection beyond that by rapid reperfusion of acute myocardial infarction is emphasized. Then, pathomechanisms of myocardial ischemia/reperfusion to the myocardium and the coronary circulation and the different modes of cell death in myocardial infarction are characterized. Different mechanical and pharmacological interventions to protect the ischemic/reperfused myocardium in elective percutaneous coronary interventions and coronary artery bypass grafting, in acute myocardial infarction and in cardiotoxicity from cancer therapy are detailed. The second part keeps the focus on ROS providing a comprehensive overview of molecular and cellular mechanisms involved in ischemia/reperfusion injury. Starting from mitochondria as the main sources and targets of ROS in ischemic/reperfused myocardium, a complex network of cellular and extracellular processes is discussed, including relationships with Ca2+ homeostasis, thiol group redox balance, hydrogen sulfide modulation, cross-talk with NAPDH oxidases, exosomes, cytokines and growth factors. While mechanistic insights are needed to improve our current therapeutic approaches, advancements in knowledge of ROS-mediated processes indicate that detrimental facets of oxidative stress are opposed by ROS requirement for physiological and protective reactions. This inevitable contrast is likely to underlie unsuccessful clinical trials and limits the development of novel cardioprotective interventions simply based upon ROS removal.

Metabolomics Point out the Effects of Carfilzomib on Aromatic Amino Acid Biosynthesis and Degradation.

(1) Carfilzomib (Cfz) is an antineoplastic agent indicated for the treatment of multiple myeloma. However, its beneficial action is attenuated by the occurrence of cardiotoxicity and nephrotoxicity as the most common adverse effects. Presently, there is well-established knowledge on the pathomechanisms related to these side effects; however, the research on the metabolic alterations provoked by the drug is limited. (2) An in vivo simulation of Cfz-induced toxicity was developed in (i) Cfz-treated and (ii) control mice. An RP-HRMS-based protocol and an advanced statistical treatment were used to investigate the impact of Cfz on the non-polar metabolome. (3) The differential analysis classified the Cfz-treated and control mice and resulted in a significant number of identified biomarkers with AUC > 0.9. The drug impaired the biosynthesis and degradation of aromatic amino acids (AAA) and led to alterations of uremic toxins in the renal and urine levels. Furthermore, the renal degradation of tryptophan was affected, inducing its degradation via the kynurenine pathway. (4) The renal levels of metabolites showed impaired excretion and degradation of AAAs. Cfz was, finally, correlated with the biosynthesis of renal dopamine, explaining the biochemical causes of water and ion retention and the increase in systolic pressure.

Synergistic Pulmonoprotective Effect of Natural Prolyl Oligopeptidase Inhibitors in In Vitro and In Vivo Models of Acute Respiratory Distress Syndrome.

Acute respiratory distress syndrome (ARDS) is a highly morbid inflammatory lung disease with limited pharmacological interventions. The present study aims to evaluate and compare the potential pulmonoprotective effects of natural prolyl oligopeptidase (POP) inhibitors namely rosmarinic acid (RA), chicoric acid (CA), epigallocatechin-3-gallate (EGCG) and gallic acid (GA), against lipopolysaccharide (LPS)-induced ARDS. Cell viability and expression of pro-inflammatory mediators were measured in RAW264.7 cells and in primary murine lung epithelial and bone marrow cells. Nitric oxide (NO) production was also assessed in unstimulated and LPS-stimulated RAW264.7 cells. For subsequent in vivo experiments, the two natural products (NPs) with the most favorable effects, RA and GA, were selected. Protein, cell content and lipid peroxidation levels in bronchoalveolar lavage fluid (BALF), as well as histopathological changes and respiratory parameters were evaluated in LPS-challenged mice. Expression of key mediators involved in ARDS pathophysiology was detected by Western blotting. RA and GA favorably reduced gene expression of pro-inflammatory mediators in vitro, while GA decreased NO production in macrophages. In LPS-challenged mice, RA and GA co-administration improved respiratory parameters, reduced cell and protein content and malondialdehyde (MDA) levels in BALF, decreased vascular cell adhesion molecule-1 (VCAM-1) and the inducible nitric oxide synthase (iNOS) protein expression, activated anti-apoptotic mechanisms and down-regulated POP in the lung. Conclusively, these synergistic pulmonoprotective effects of RA and GA co-administration could render them a promising prophylactic/therapeutic pharmacological intervention against ARDS.

Association of hydroxytyrosol enriched olive oil with vascular function in chronic coronary disease.

BACKGROUND: Hydroxytyrosol reduces low-density lipoprotein oxidation, contributing to prevention of atherosclerosis progression. METHODS: In a prospective, crossover, double-blind, placebo-controlled trial, 30 chronic coronary artery syndrome (CCAS) patients were randomized to 4 capsules/day, containing 412.5 mg olive oil with 2.5 mg hydroxytyrosol (OOHT) each one or placebo for 1 month and then were crossed over to the alternate treatment (placebo or OOHT). We measured (a) perfused boundary region (PBR) of the sublingual arterial microvessels (increased PBR indicates reduced glycocalyx thickness), (b) flow-mediated dilation (FMD), (c) Coronary Flow Reserve (CFR) and markers of LV diastolic function by Doppler echocardiography, (d) pulse wave velocity (PWV), and (e) oxidative stress, inflammatory biomarkers and blood lipids at baseline and after treatment. RESULTS: Treatment with OOHT improved PBR, FMD, CFR and PWV compared to baseline (1.8 ± .3 vs. 1.7 ± .4 µm, p = .040, 3.7 ± 2.1 vs. 6.5% ± 2.3%, p < .001, 2.3 ± .4 vs. 2.5 ± .4, p = .030 and 11.1 ± 1.8 vs. 11.8 ± 2.3 m/s, p = .002) while there was no effect after placebo (p = NS). No effect of OOHT treatment was observed on blood pressure. There was a parallel improvement of E' of the mitral annulus and deceleration time of the E wave of mitral inflow after OOHT (p < .05) but not after placebo. Compared to baseline, treatment with OOHT reduced malondialdehyde, a marker of lipid peroxidation, oxidized LDL, triglycerides, PCSK9 and CRP blood levels (p < .05) in contrast to placebo. CONCLUSIONS: Hydroxytyrosol-enriched olive oil may have beneficial effects on endothelial, arterial and LV diastolic function likely by reducing oxidative and inflammatory burden in CCAS, though further studies are needed to confirm this mechanism.

Interaction of Cardiovascular Nonmodifiable Risk Factors, Comorbidities and Comedications With Ischemia/Reperfusion Injury and Cardioprotection by Pharmacological Treatments and Ischemic Conditioning.

Preconditioning, postconditioning, and remote conditioning of the myocardium enhance the ability of the heart to withstand a prolonged ischemia/reperfusion insult and the potential to provide novel therapeutic paradigms for cardioprotection. While many signaling pathways leading to endogenous cardioprotection have been elucidated in experimental studies over the past 30 years, no cardioprotective drug is on the market yet for that indication. One likely major reason for this failure to translate cardioprotection into patient benefit is the lack of rigorous and systematic preclinical evaluation of promising cardioprotective therapies prior to their clinical evaluation, since ischemic heart disease in humans is a complex disorder caused by or associated with cardiovascular risk factors and comorbidities. These risk factors and comorbidities induce fundamental alterations in cellular signaling cascades that affect the development of ischemia/reperfusion injury and responses to cardioprotective interventions. Moreover, some of the medications used to treat these comorbidities may impact on cardioprotection by again modifying cellular signaling pathways. The aim of this article is to review the recent evidence that cardiovascular risk factors as well as comorbidities and their medications may modify the response to cardioprotective interventions. We emphasize the critical need for taking into account the presence of cardiovascular risk factors as well as comorbidities and their concomitant medications when designing preclinical studies for the identification and validation of cardioprotective drug targets and clinical studies. This will hopefully maximize the success rate of developing rational approaches to effective cardioprotective therapies for the majority of patients with multiple comorbidities. SIGNIFICANCE STATEMENT: Ischemic heart disease is a major cause of mortality; however, there are still no cardioprotective drugs on the market. Most studies on cardioprotection have been undertaken in animal models of ischemia/reperfusion in the absence of comorbidities; however, ischemic heart disease develops with other systemic disorders (e.g., hypertension, hyperlipidemia, diabetes, atherosclerosis). Here we focus on the preclinical and clinical evidence showing how these comorbidities and their routine medications affect ischemia/reperfusion injury and interfere with cardioprotective strategies.

Platelet-Mediated Transfer of Cardioprotection by Remote Ischemic Conditioning and Its Abrogation by Aspirin But Not by Ticagrelor.

PURPOSE: The role of platelets during myocardial ischemia/reperfusion (I/R) is ambivalent. They contribute to injury but also to cardioprotection. Repeated blood flow restriction and reperfusion in a tissue/organ remote from the heart (remote ischemic conditioning, RIC) reduce myocardial I/R injury and attenuate platelet activation. Whether or not platelets mediate RIC's cardioprotective signal is currently unclear. METHODS AND RESULTS: Venous blood from healthy volunteers (without or with pretreatment of 500/1000 mg aspirin or 180 mg ticagrelor orally, 2-3 h before the study, n = 18 each) was collected before and after RIC (3 × 5 min blood pressure cuff inflation at 200 mmHg on the left upper arm/5 min deflation). Washed platelets were isolated. Platelet-poor plasma was used to prepare plasma-dialysates. Platelets (25 × 103/µL) or plasma-dialysates (1:10) prepared before and after RIC from untreated versus aspirin- or ticagrelor-pretreated volunteers, respectively, were infused into isolated buffer-perfused rat hearts. Hearts were subjected to global 30 min/120 min I/R. Infarct size was stained. Infarct size was less with infusion of platelets/plasma-dialysate after RIC (18 ± 7%/23 ± 9% of ventricular mass) than with platelets/plasma-dialysate before RIC (34 ± 7%/33 ± 8%). Aspirin pretreatment abrogated the transfer of RIC's cardioprotection by platelets (after/before RIC, 34 ± 7%/33 ± 7%) but only attenuated that by plasma-dialysate (after/before RIC, 26 ± 8%/32 ± 5%). Ticagrelor pretreatment induced an in vivo formation of cardioprotective factor(s) per se (platelets/plasma-dialysate before RIC, 26 ± 7%/26 ± 7%) but did not impact on RIC's cardioprotection by platelets/plasma-dialysate (20 ± 7%/21 ± 5%). CONCLUSION: Platelets serve as carriers for RIC's cardioprotective signal through an aspirin-sensitive and thus cyclooxygenase-dependent mechanism. The P2Y12 inhibitor ticagrelor per se induces a humoral cardioprotective signal.

The effects of ischaemic conditioning on lung ischaemia-reperfusion injury.

Ischaemia-reperfusion injury (IRI) encompasses the deleterious effects on cellular function and survival that result from the restoration of organ perfusion. Despite their unique tolerance to ischaemia and hypoxia, afforded by their dual (pulmonary and bronchial) circulation as well as direct oxygen diffusion from the airways, lungs are particularly susceptible to IRI (LIRI). LIRI may be observed in a variety of clinical settings, including lung transplantation, lung resections, cardiopulmonary bypass during cardiac surgery, aortic cross-clamping for abdominal aortic aneurysm repair, as well as tourniquet application for orthopaedic operations. It is a diagnosis of exclusion, manifesting clinically as acute lung injury (ALI) or acute respiratory distress syndrome (ARDS). Ischaemic conditioning (IC) signifies the original paradigm of treating IRI. It entails the application of short, non-lethal ischemia and reperfusion manoeuvres to an organ, tissue, or arterial territory, which activates mechanisms that reduce IRI. Interestingly, there is accumulating experimental and preliminary clinical evidence that IC may ameliorate LIRI in various pathophysiological contexts. Considering the detrimental effects of LIRI, ranging from ALI following lung resections to primary graft dysfunction (PGD) after lung transplantation, the association of these entities with adverse outcomes, as well as the paucity of protective or therapeutic interventions, IC holds promise as a safe and effective strategy to protect the lung. This article aims to provide a narrative review of the existing experimental and clinical evidence regarding the effects of IC on LIRI and prompt further investigation to refine its clinical application.

Myocardial Protection and Current Cancer Therapy: Two Opposite Targets with Inevitable Cost.

Myocardial protection against ischemia/reperfusion injury (IRI) is mediated by various ligands, activating different cellular signaling cascades. These include classical cytosolic mediators such as cyclic-GMP (c-GMP), various kinases such as Phosphatydilinositol-3- (PI3K), Protein Kinase B (Akt), Mitogen-Activated-Protein- (MAPK) and AMP-activated (AMPK) kinases, transcription factors such as signal transducer and activator of transcription 3 (STAT3) and bioactive molecules such as vascular endothelial growth factor (VEGF). Most of the aforementioned signaling molecules constitute targets of anticancer therapy; as they are also involved in carcinogenesis, most of the current anti-neoplastic drugs lead to concomitant weakening or even complete abrogation of myocardial cell tolerance to ischemic or oxidative stress. Furthermore, many anti-neoplastic drugs may directly induce cardiotoxicity via their pharmacological effects, or indirectly via their cardiovascular side effects. The combination of direct drug cardiotoxicity, indirect cardiovascular side effects and neutralization of the cardioprotective defense mechanisms of the heart by prolonged cancer treatment may induce long-term ventricular dysfunction, or even clinically manifested heart failure. We present a narrative review of three therapeutic interventions, namely VEGF, proteasome and Immune Checkpoint inhibitors, having opposing effects on the same intracellular signal cascades thereby affecting the heart. Moreover, we herein comment on the current guidelines for managing cardiotoxicity in the clinical setting and on the role of cardiovascular confounders in cardiotoxicity.

An Untargeted Metabolomics Approach on Carfilzomib-Induced Nephrotoxicity.

BACKGROUND: Carfilzomib (Cfz) is an anti-cancer drug related to cardiorenal adverse events, with cardiovascular and renal complications limiting its clinical use. Despite the important progress concerning the discovery of the underlying causes of Cfz-induced nephrotoxicity, the molecular/biochemical background is still not well clarified. Furthermore, the number of metabolomics-based studies concerning Cfz-induced nephrotoxicity is limited. METHODS: A metabolomics UPLC-HRMS-DIA methodology was applied to three bio-sample types i.e., plasma, kidney, and urine, obtained from two groups of mice, namely (i) Cfz (8 mg Cfz/ kg) and (ii) Control (0.9% NaCl) (n = 6 per group). Statistical analysis, involving univariate and multivariate tools, was applied for biomarker detection. Furthermore, a sub-study was developed, aiming to estimate metabolites' correlation among bio-samples, and to enlighten potential mechanisms. RESULTS: Cfz mostly affects the kidneys and urine metabolome. Fifty-four statistically important metabolites were discovered, and some of them have already been related to renal diseases. Furthermore, the correlations between bio-samples revealed patterns of metabolome alterations due to Cfz. CONCLUSIONS: Cfz causes metabolite retention in kidney and dysregulates (up and down) several metabolites associated with the occurrence of inflammation and oxidative stress.

Mineralocorticoid Receptor Pathway Is a Key Mediator of Carfilzomib-induced Nephrotoxicity: Preventive Role of Eplerenone.

Carfilzomib is an irreversible proteasome inhibitor indicated for relapsed/refractory multiple myeloma. Carfilzomib toxicity includes renal adverse effects (RAEs) of obscure pathobiology. Therefore, we investigated the mechanisms of nephrotoxicity developed by Carfilzomib. In a first experimental series, we used our previously established in vivo mouse models of Carfilzomib cardiotoxicity, that incorporated 2 and 4 doses of Carfilzomib, to identify whether Carfilzomib affects renal pathways. Hematology and biochemical analyses were performed, while kidneys underwent histological and molecular analyses. In a second and third experimental series, the 4 doses protocol was repeated for 24 hours urine collection and proteomic/metabolomic analyses. To test an experimental intervention, primary murine collecting duct tubular epithelial cells were treated with Carfilzomib and/or Eplerenone and Metformin. Finally, Eplerenone was orally co-administered with Carfilzomib daily (165 mg/kg) in the 4 doses protocol. We additionally used material from 7 patients to validate our findings and patients underwent biochemical analysis and assessment of renal mineralocorticoid receptor (MR) axis activation. In vivo screening showed that Carfilzomib-induced renal histological deficits and increased serum creatinine, urea, NGAL levels, and proteinuria only in the 4 doses protocol. Carfilzomib decreased diuresis, altered renal metabolism, and activated MR axis. This was consistent with the cytotoxicity found in primary murine collecting duct tubular epithelial cells, whereas Carfilzomib + Eplerenone co-administration abrogated Carfilzomib-related nephrotoxic effects in vitro and in vivo. Renal SGK-1, a marker of MR activation, increased in patients with Carfilzomib-related RAEs. Conclusively, Carfilzomib-induced renal MR/SGK-1 activation orchestrates RAEs and water retention both in vivo and in the clinical setting. MR blockade emerges as a potential therapeutic approach against Carfilzomib-related nephrotoxicity.

Endothelial Dysfunction Is Associated with Decreased Nitric Oxide Bioavailability in Dysglycaemic Subjects and First-Degree Relatives of Type 2 Diabetic Patients.

Oxidative stress plays an important role in the pathogenesis of diabetes. We investigated oxidative stress and nitrite/nitrate concentrations at baseline and during postprandial hyperglycaemia in 40 first-degree relatives (FDRs) of diabetic patients with normal oral glucose tolerance test (OGTT) results, 40 subjects with abnormal OGTT results (dysglycaemic) and 20 subjects with normal OGTT results (normoglycaemic). Malondialdehyde (MDA), protein carbonyls (PCs), nitrite/nitrate plasma levels, the perfused boundary region (PBR­Glycocheck) of the sublingual microvessels, a marker of glycocalyx integrity, coronary flow reserve (CFR) and left ventricular global longitudinal strain (GLS) were assessed at 0 and 120 min of the OGTT. Insulin sensitivity was evaluated using Matsuda and the insulin sensitivity index (ISI). In all subjects, there were no significant changes in MDA or PC after the OGTT (p > 0.05). Compared with normoglycaemic subjects, FDRs and dysglycaemic subjects had significantly decreased nitrite/nitrate levels (−3% vs. −24% vs. −30%, respectively), an increased PBR and reduced CFR and GLS at 120 min (p < 0.05). The percent reduction in nitrite/nitrate was associated with abnormal Matsuda and ISI results, reversely related with the percent increase in PBR (r = −0.60) and positively related with the percent decrease in CFR (r = 0.39) and GLS (r = 0.48) (p < 0.05). Insulin resistance is associated with reduced nitric oxide bioavailability and coronary and myocardial dysfunction in FDRs and dysglycaemic subjects.

Cardioprotection by selective SGLT-2 inhibitors in a non-diabetic mouse model of myocardial ischemia/reperfusion injury: a class or a drug effect?

Major clinical trials with sodium glucose co-transporter-2 inhibitors (SGLT-2i) exhibit protective effects against heart failure events, whereas inconsistencies regarding the cardiovascular death outcomes are observed. Therefore, we aimed to compare the selective SGLT-2i empagliflozin (EMPA), dapagliflozin (DAPA) and ertugliflozin (ERTU) in terms of infarct size (IS) reduction and to reveal the cardioprotective mechanism in healthy non-diabetic mice. C57BL/6 mice randomly received vehicle, EMPA (10 mg/kg/day) and DAPA or ERTU orally at the stoichiometrically equivalent dose (SED) for 7 days. 24 h-glucose urinary excretion was determined to verify SGLT-2 inhibition. IS of the region at risk was measured after 30 min ischemia (I), and 120 min reperfusion (R). In a second series, the ischemic myocardium was collected (10th min of R) for shotgun proteomics and evaluation of the cardioprotective signaling. In a third series, we evaluated the oxidative phosphorylation capacity (OXPHOS) and the mitochondrial fatty acid oxidation capacity by measuring the respiratory rates. Finally, Stattic, the STAT-3 inhibitor and wortmannin were administered in both EMPA and DAPA groups to establish causal relationships in the mechanism of protection. EMPA, DAPA and ERTU at the SED led to similar SGLT-2 inhibition as inferred by the significant increase in glucose excretion. EMPA and DAPA but not ERTU reduced IS. EMPA preserved mitochondrial functionality in complex I&II linked oxidative phosphorylation. EMPA and DAPA treatment led to NF-kB, RISK, STAT-3 activation and the downstream apoptosis reduction coinciding with IS reduction. Stattic and wortmannin attenuated the cardioprotection afforded by EMPA and DAPA. Among several upstream mediators, fibroblast growth factor-2 (FGF-2) and caveolin-3 were increased by EMPA and DAPA treatment. ERTU reduced IS only when given at the double dose of the SED (20 mg/kg/day). Short-term EMPA and DAPA, but not ERTU administration at the SED reduce IS in healthy non-diabetic mice. Cardioprotection is not correlated to SGLT-2 inhibition, is STAT-3 and PI3K dependent and associated with increased FGF-2 and Cav-3 expression.