Multiomics analysis identifies novel facilitators of human dopaminergic neuron differentiation.

Midbrain dopaminergic neurons (mDANs) control voluntary movement, cognition, and reward behavior under physiological conditions and are implicated in human diseases such as Parkinson's disease (PD). Many transcription factors (TFs) controlling human mDAN differentiation during development have been described, but much of the regulatory landscape remains undefined. Using a tyrosine hydroxylase (TH) human iPSC reporter line, we here generate time series transcriptomic and epigenomic profiles of purified mDANs during differentiation. Integrative analysis predicts novel regulators of mDAN differentiation and super-enhancers are used to identify key TFs. We find LBX1, NHLH1 and NR2F1/2 to promote mDAN differentiation and show that overexpression of either LBX1 or NHLH1 can also improve mDAN specification. A more detailed investigation of TF targets reveals that NHLH1 promotes the induction of neuronal miR-124, LBX1 regulates cholesterol biosynthesis, and NR2F1/2 controls neuronal activity.

Mitochondrial MDM2 Regulates Respiratory Complex I Activity Independently of p53.

Accumulating evidence indicates that the MDM2 oncoprotein promotes tumorigenesis beyond its canonical negative effects on the p53 tumor suppressor, but these p53-independent functions remain poorly understood. Here, we show that a fraction of endogenous MDM2 is actively imported in mitochondria to control respiration and mitochondrial dynamics independently of p53. Mitochondrial MDM2 represses the transcription of NADH-dehydrogenase 6 (MT-ND6) in vitro and in vivo, impinging on respiratory complex I activity and enhancing mitochondrial ROS production. Recruitment of MDM2 to mitochondria increases during oxidative stress and hypoxia. Accordingly, mice lacking MDM2 in skeletal muscles exhibit higher MT-ND6 levels, enhanced complex I activity, and increased muscular endurance in mild hypoxic conditions. Furthermore, increased mitochondrial MDM2 levels enhance the migratory and invasive properties of cancer cells. Collectively, these data uncover a previously unsuspected function of the MDM2 oncoprotein in mitochondria that play critical roles in skeletal muscle physiology and may contribute to tumor progression.

Polygenic Risk Scores Validated in Patient-Derived Cells Stratify for Mitochondrial Subtypes of Parkinson's Disease.

OBJECTIVE: The aim of our study is to better understand the genetic architecture and pathological mechanisms underlying neurodegeneration in idiopathic Parkinson's disease (iPD). We hypothesized that a fraction of iPD patients may harbor a combination of common variants in nuclear-encoded mitochondrial genes ultimately resulting in neurodegeneration. METHODS: We used mitochondria-specific polygenic risk scores (mitoPRSs) and created pathway-specific mitoPRSs using genotype data from different iPD case-control datasets worldwide, including the Luxembourg Parkinson's Study (412 iPD patients and 576 healthy controls) and COURAGE-PD cohorts (7,270 iPD cases and 6,819 healthy controls). Cellular models from individuals stratified according to the most significant mitoPRS were subsequently used to characterize different aspects of mitochondrial function. RESULTS: Common variants in genes regulating Oxidative Phosphorylation (OXPHOS-PRS) were significantly associated with a higher PD risk in independent cohorts (Luxembourg Parkinson's Study odds ratio, OR = 1.31[1.14-1.50], p-value = 5.4e-04; COURAGE-PD OR = 1.23[1.18-1.27], p-value = 1.5e-29). Functional analyses in fibroblasts and induced pluripotent stem cells-derived neuronal progenitors revealed significant differences in mitochondrial respiration between iPD patients with high or low OXPHOS-PRS (p-values < 0.05). Clinically, iPD patients with high OXPHOS-PRS have a significantly earlier age at disease onset compared to low-risk patients (false discovery rate [FDR]-adj p-value = 0.015), similar to prototypic monogenic forms of PD. Finally, iPD patients with high OXPHOS-PRS responded more effectively to treatment with mitochondrially active ursodeoxycholic acid. INTERPRETATION: OXPHOS-PRS may provide a precision medicine tool to stratify iPD patients into a pathogenic subgroup genetically defined by specific mitochondrial impairment, making these individuals eligible for future intelligent clinical trial designs. ANN NEUROL 2024;96:133-149.

Closed Loop Stimulation reduces the incidence of atrial high-rate episodes compared to conventional rate-adaptive pacing in patients with sinus node dysfunctions.

BACKGROUND AND AIMS: Subclinical atrial fibrillation (AF) is associated with increased risk of progression to clinical AF, stroke, and cardiovascular death. We hypothesized that in pacemaker patients requiring dual-chamber rate-adaptive (DDDR) pacing, Closed Loop Stimulation (CLS) integrated into the circulatory control system through intracardiac impedance monitoring would reduce the occurrence of atrial high-rate episodes (AHREs) compared to conventional DDDR pacing. METHODS: Patients with sinus node dysfunctions (SND) and an implanted pacemaker or defibrillator were randomly allocated to dual-chamber CLS (n=612) or accelerometer-based DDDR pacing (n=598) and followed for 3 years. The primary endpoint was time to the composite endpoint of first AHRE lasting ≥6 minutes, stroke, or transient ischemic attack (TIA). All AHREs were independently adjudicated using intracardiac electrograms. RESULTS: The incidence of the primary endpoint was lower in the CLS arm (50.6%) than in the DDDR arm (55.7%), primarily due to the reduction in AHREs lasting between 6 hours and 7 days. Unadjusted site-stratified hazard ratio (HR) for CLS versus DDDR was 0.84 (95%-CI, 0.72-0.99; p=0.035). After adjusting for CHA2DS2-VASc score, the HR remained 0.84 (95%-CI, 0.71-0.99; p=0.033). In subgroup analyses, the incremental benefit of CLS was greatest in patients without atrioventricular block (HR, 0.76; p=0.006) and in patients without AF history (HR, 0.73; p=0.010). The contribution of stroke/TIA to the primary endpoint (1.3%) was low and not statistically different between study arms. CONCLUSIONS: Dual-chamber CLS in patients with SND is associated with a significantly lower AHRE incidence than conventional DDDR pacing.

Chromatin-Bound MDM2 Regulates Serine Metabolism and Redox Homeostasis Independently of p53.

The mouse double minute 2 (MDM2) oncoprotein is recognized as a major negative regulator of the p53 tumor suppressor, but growing evidence indicates that its oncogenic activities extend beyond p53. Here, we show that MDM2 is recruited to chromatin independently of p53 to regulate a transcriptional program implicated in amino acid metabolism and redox homeostasis. Identification of MDM2 target genes at the whole-genome level highlights an important role for ATF3/4 transcription factors in tethering MDM2 to chromatin. MDM2 recruitment to chromatin is a tightly regulated process that occurs during oxidative stress and serine/glycine deprivation and is modulated by the pyruvate kinase M2 (PKM2) metabolic enzyme. Depletion of endogenous MDM2 in p53-deficient cells impairs serine/glycine metabolism, the NAD(+)/NADH ratio, and glutathione (GSH) recycling, impacting their redox state and tumorigenic potential. Collectively, our data illustrate a previously unsuspected function of chromatin-bound MDM2 in cancer cell metabolism.

Combination of an implantable defibrillator multi-sensor heart failure index and an apnea index for the prediction of atrial high-rate events.

AIMS: Patients with atrial fibrillation frequently experience sleep disorder breathing, and both conditions are highly prevalent in presence of heart failure (HF). We explored the association between the combination of an HF and a sleep apnoea (SA) index and the incidence of atrial high-rate events (AHRE) in patients with implantable defibrillators (ICDs). METHODS AND RESULTS: Data were prospectively collected from 411 consecutive HF patients with ICD. The IN-alert HF state was measured by the multi-sensor HeartLogic Index (>16), and the ICD-measured Respiratory Disturbance Index (RDI) was computed to identify severe SA. The endpoints were as follows: daily AHRE burden of ≥5 min, ≥6 h, and ≥23 h. During a median follow-up of 26 months, the time IN-alert HF state was 13% of the total observation period. The RDI value was ≥30 episodes/h (severe SA) during 58% of the observation period. An AHRE burden of ≥5 min/day was documented in 139 (34%) patients, ≥6 h/day in 89 (22%) patients, and ≥23 h/day in 68 (17%) patients. The IN-alert HF state was independently associated with AHRE regardless of the daily burden threshold: hazard ratios from 2.17 for ≥5 min/day to 3.43 for ≥23 h/day (P < 0.01). An RDI ≥ 30 episodes/h was associated only with AHRE burden ≥5 min/day [hazard ratio 1.55 (95% confidence interval: 1.11-2.16), P = 0.001]. The combination of IN-alert HF state and RDI ≥ 30 episodes/h accounted for only 6% of the follow-up period and was associated with high rates of AHRE occurrence (from 28 events/100 patient-years for AHRE burden ≥5 min/day to 22 events/100 patient-years for AHRE burden ≥23 h/day). CONCLUSIONS: In HF patients, the occurrence of AHRE is independently associated with the ICD-measured IN-alert HF state and RDI ≥ 30 episodes/h. The coexistence of these two conditions occurs rarely but is associated with a very high rate of AHRE occurrence. CLINICAL TRIAL REGISTRATION: URL: http://clinicaltrials.gov/Identifier: NCT02275637.

Performance of a multi-sensor implantable defibrillator algorithm for heart failure monitoring in the presence of atrial fibrillation.

AIMS: The HeartLogic Index combines data from multiple implantable cardioverter defibrillators (ICDs) sensors and has been shown to accurately stratify patients at risk of heart failure (HF) events. We evaluated and compared the performance of this algorithm during sinus rhythm and during long-lasting atrial fibrillation (AF). METHODS AND RESULTS: HeartLogic was activated in 568 ICD patients from 26 centres. We found periods of ≥30 consecutive days with an atrial high-rate episode (AHRE) burden <1 h/day and periods with an AHRE burden ≥20 h/day. We then identified patients who met both criteria during the follow-up (AHRE group, n = 53), to allow pairwise comparison of periods. For control purposes, we identified patients with an AHRE burden <1 h throughout their follow-up and implemented 2:1 propensity score matching vs. the AHRE group (matched non-AHRE group, n = 106). In the AHRE group, the rate of alerts was 1.2 [95% confidence interval (CI): 1.0-1.5]/patient-year during periods with an AHRE burden <1 h/day and 2.0 (95% CI: 1.5-2.6)/patient-year during periods with an AHRE-burden ≥20 h/day (P = 0.004). The rate of HF hospitalizations was 0.34 (95% CI: 0.15-0.69)/patient-year during IN-alert periods and 0.06 (95% CI: 0.02-0.14)/patient-year during OUT-of-alert periods (P < 0.001). The IN/OUT-of-alert state incidence rate ratio of HF hospitalizations was 8.59 (95% CI: 1.67-55.31) during periods with an AHRE burden <1 h/day and 2.70 (95% CI: 1.01-28.33) during periods with an AHRE burden ≥20 h/day. In the matched non-AHRE group, the rate of HF hospitalizations was 0.29 (95% CI: 0.12-0.60)/patient-year during IN-alert periods and 0.04 (95% CI: 0.02-0.08)/patient-year during OUT-of-alert periods (P < 0.001). The incidence rate ratio was 7.11 (95% CI: 2.19-22.44). CONCLUSION: Patients received more alerts during periods of AF. The ability of the algorithm to identify increased risk of HF events was confirmed during AF, despite a lower IN/OUT-of-alert incidence rate ratio in comparison with non-AF periods and non-AF patients. CLINICAL TRIAL REGISTRATION: http://clinicaltrials.gov/Identifier: NCT02275637.

Reducing Carbapenem-Resistant Enterobacteriaceae Using the Targeted Solution Tool: A Quality Improvement Project.

BACKGROUND: Carbapenem-resistant Enterobacteriaceae (CRE) is a worldwide urgent health problem. Hand hygiene (HH) is an effective intervention to reduce the spread of CRE. LOCAL PROBLEM: In 2017, an increase in the rate of health care-associated (HA) CRE colonization was observed in a large multiorgan transplant center in Italy. This study aimed to reduce the HA-CRE colonization rates by improving HH compliance. METHODS: A pre-/post-intervention project was conducted from November 2017 through December 2020. INTERVENTIONS: The DMAIC (Define, Measure, Analyze, Improve, and Control) framework was used to implement the HH Targeted Solution Tool (TST). RESULTS: Hand hygiene compliance increased from 49% to 76.9% after the Improve phase ( P = .0001), and to 81.9% after the second Control phase ( P = .0001). The rate of HA-CRE decreased from 24.9% to 5.6% ( P = .0001). CONCLUSIONS: Using the DMAIC framework to implement the TST can result in significant improvements in HH compliance and HA-CRE colonization rates.

Impaired mitochondrial-endoplasmic reticulum interaction and mitophagy in Miro1-mutant neurons in Parkinson's disease.

Mitochondrial Rho GTPase 1 (Miro1) protein is a well-known adaptor for mitochondrial transport and also regulates mitochondrial quality control and function. Furthermore, Miro1 was associated with mitochondrial-endoplasmic reticulum (ER) contact sites (MERCs), which are key regulators of cellular calcium homeostasis and the initiation of autophagy. Impairments of these mechanisms were linked to neurodegeneration in Parkinson's disease (PD). We recently revealed that PD fibroblasts harboring Miro1 mutations displayed dysregulations in MERC organization and abundance, affecting mitochondrial homeostasis and clearance. We hypothesize that mutant Miro1 impairs the function of MERCs and mitochondrial dynamics, altering neuronal homeostasis and integrity in PD. PD skin fibroblasts harboring the Miro1-R272Q mutation were differentiated into patient-derived neurons. Live-cell imaging and immunocytochemistry were used to study mitophagy and the organization and function of MERCs. Markers of autophagy or mitochondrial function were assessed by western blotting. Quantification of organelle juxtapositions revealed an increased number of MERCs in patient-derived neurons. Live-cell imaging results showed alterations of mitochondrial dynamics and increased sensitivity to calcium stress, as well as reduced mitochondrial clearance. Finally, western blot analysis indicated a blockage of the autophagy flux in Miro1-mutant neurons. Miro1-mutant neurons display altered ER-mitochondrial tethering compared with control neurons. This alteration likely interferes with proper MERC function, contributing to a defective autophagic flux and cytosolic calcium handling capacity. Moreover, mutant Miro1 affects mitochondrial dynamics in neurons, which may result in disrupted mitochondrial turnover and altered mitochondrial movement.

Parkin Deficiency Impairs Mitochondrial DNA Dynamics and Propagates Inflammation.

BACKGROUND: Mutations in the E3 ubiquitin ligase parkin cause autosomal recessive Parkinson's disease (PD). Together with PTEN-induced kinase 1 (PINK1), parkin regulates the clearance of dysfunctional mitochondria. New mitochondria are generated through an interplay of nuclear- and mitochondrial-encoded proteins, and recent studies suggest that parkin influences this process at both levels. In addition, parkin was shown to prevent mitochondrial membrane permeability, impeding mitochondrial DNA (mtDNA) escape and subsequent neuroinflammation. However, parkin's regulatory roles independent of mitophagy are not well described in patient-derived neurons. OBJECTIVES: We sought to investigate parkin's role in preventing neuronal mtDNA dyshomeostasis, release, and glial activation at the endogenous level. METHODS: We generated induced pluripotent stem cell (iPSC)-derived midbrain neurons from PD patients with parkin (PRKN) mutations and healthy controls. Live-cell imaging, proteomic, mtDNA integrity, and gene expression analyses were employed to investigate mitochondrial biogenesis and genome maintenance. To assess neuroinflammation, we performed single-nuclei RNA sequencing in postmortem tissue and quantified interleukin expression in mtDNA/lipopolysaccharides (LPS)-treated iPSC-derived neuron-microglia co-cultures. RESULTS: Neurons from patients with PRKN mutations revealed deficits in the mitochondrial biogenesis pathway, resulting in mtDNA dyshomeostasis. Moreover, the energy sensor sirtuin 1, which controls mitochondrial biogenesis and clearance, was downregulated in parkin-deficient cells. Linking mtDNA disintegration to neuroinflammation, in postmortem midbrain with PRKN mutations, we confirmed mtDNA dyshomeostasis and detected an upregulation of microglia overexpressing proinflammatory cytokines. Finally, parkin-deficient neuron-microglia co-cultures elicited an enhanced immune response when exposed to mtDNA/LPS. CONCLUSIONS: Our findings suggest that parkin coregulates mitophagy, mitochondrial biogenesis, and mtDNA maintenance pathways, thereby protecting midbrain neurons from neuroinflammation and degeneration. © 2022 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

Parkinson's Disease Phenotypes in Patient Neuronal Cultures and Brain Organoids Improved by 2-Hydroxypropyl-ß-Cyclodextrin Treatment.

BACKGROUND: The etiology of Parkinson's disease (PD) is only partially understood despite the fact that environmental causes, risk factors, and specific gene mutations are contributors to the disease. Biallelic mutations in the phosphatase and tensin homolog (PTEN)-induced putative kinase 1 (PINK1) gene involved in mitochondrial homeostasis, vesicle trafficking, and autophagy are sufficient to cause PD. OBJECTIVES: We sought to evaluate the difference between controls' and PINK1 patients' derived neurons in their transition from neuroepithelial stem cells to neurons, allowing us to identify potential pathways to target with repurposed compounds. METHODS: Using two-dimensional and three-dimensional models of patients' derived neurons we recapitulated PD-related phenotypes. We introduced the usage of midbrain organoids for testing compounds. Using Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)/CRISPR-associated protein 9 (Cas9), we corrected the point mutations of three patients' derived cells. We evaluated the effect of the selected compound in a mouse model. RESULTS: PD patient-derived cells presented differences in their energetic profile, imbalanced proliferation, apoptosis, mitophagy, and a reduced differentiation efficiency to tyrosine hydroxylase positive (TH+) neurons compared to controls' cells. Correction of a patient's point mutation ameliorated the metabolic properties and neuronal firing rates as well as reversing the differentiation phenotype, and reducing the increased astrocytic levels. Treatment with 2-hydroxypropyl-ß-cyclodextrin increased the autophagy and mitophagy capacity of neurons concomitant with an improved dopaminergic differentiation of patient-specific neurons in midbrain organoids and ameliorated neurotoxicity in a mouse model. CONCLUSION: We show that treatment with a repurposed compound is sufficient for restoring the impaired dopaminergic differentiation of PD patient-derived cells. © 2021 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

BAG6 promotes PINK1 signaling pathway and is essential for mitophagy.

Bcl-2-associated athanogen-6 (BAG6) is a nucleocytoplasmic shuttling protein involved in protein quality control. We previously demonstrated that BAG6 is essential for autophagy by regulating the intracellular localization of the acetyltransferase EP300, and thus, modifying accessibility to its substrates (TP53 in the nucleus and autophagy-related proteins in the cytoplasm). Here, we investigated BAG6 localization and function in the cytoplasm. First, we demonstrated that BAG6 is localized in the mitochondria. Specifically, BAG6 is expressed in the mitochondrial matrix under basal conditions, and translocates to the outer mitochondrial membrane after mitochondrial depolarization with carbonyl cyanide m-chlorophenyl hydrazine, a mitochondrial uncoupler that induces mitophagy. In SW480 cells, the deletion of BAG6 expression abrogates its ability to induce mitophagy and PINK1 accumulation. On the reverse, its ectopic expression in LoVo colon cancer cells, which do not express endogenous BAG6, reduces the size of the mitochondria, induces mitophagy, leads to the activation of the PINK1/PARKIN pathway and to the phospho-ubiquitination of mitochondrial proteins. Finally, BAG6 contains two LIR (LC3-interacting Region) domains specifically found in receptors for selective autophagy and responsible for the interaction with LC3 and for autophagosome selectivity. Site-directed mutagenesis showed that BAG6 requires wild-type LIRs domains for its ability to stimulate mitophagy. In conclusion, we propose that BAG6 is a novel mitophagy receptor or adaptor that induces PINK1/PARKIN signaling and mitophagy in a LIR-dependent manner.

Second versus fourth generation of cryoballoon catheters: The 1STOP real-world multicenter experience.

BACKGROUND: It has been observed that the fourth-generation cryoballoon (CB4) ablation catheter increased the rate of acute real-time recordings of pulmonary vein isolation (PVI) during the ablation for the treatment of atrial fibrillation (AF). The aim of this analysis was to compare the long-term outcome results between patients treated with the CB4 and second-generation cryoballoon (CB2). METHODS: In total, 492 patients suffering from AF, underwent PVI ablation with either the CB2 or CB4 catheter within this examination of the 1STOP real-world Italian project and were included in the analysis. Specifically, 246 consecutive patients treated by CB4 were compared to 246 propensity-matched control patients who underwent PVI using CB2. RESULTS: When comparing the patient cohorts treated with CB2 versus CB4, acute success rate (99.6 ± 4.7% vs. 99.7 ± 3.6%, p = .949) and peri-procedural complications (3.7% vs.1.2%, p = .080) were similar in both groups, respectively. However, procedure time (100 vs.75 min, p < .001) and fluoroscopy duration (21 vs.17 min, p < .001) were all significantly lower in the CB4 treated patient cohort. At the 12-month follow-up, the freedom from AF recurrence after a 90-day blanking period was significant higher in the CB4 as compared with the CB2 group (93.3% vs.81.3%, p < .001). CONCLUSIONS: In summary, usage of the CB4 ablation catheter increased the rate of acute PVI recording capability and resulted in a higher rate of long-term PVI success, as demonstrated by the reduced rate of AF recurrence in comparison to the CB2 cohort at the 12-month follow-up period.

A Deeper Insight in Metal Binding to the hCtr1 N-terminus Fragment: Affinity, Speciation and Binding Mode of Binuclear Cu2+ and Mononuclear Ag+ Complex Species.

Ctr1 regulates copper uptake and its intracellular distribution. The first 14 amino acid sequence of the Ctr1 ectodomain Ctr1(1-14) encompasses the characteristic Amino Terminal Cu2+ and Ni2+ binding motif (ATCUN) as well as the bis-His binding motif (His5 and His6). We report a combined thermodynamic and spectroscopic (UV-vis, CD, EPR) study dealing with the formation of Cu2+ homobinuclear complexes with Ctr1(1-14), the percentage of which is not negligible even in the presence of a small Cu2+ excess and clearly prevails at a M/L ratio of 1.9. Ascorbate fails to reduce Cu2+ when bound to the ATCUN motif, while it reduces Cu2+ when bound to the His5-His6 motif involved in the formation of binuclear species. The histidine diade characterizes the second binding site and is thought to be responsible for ascorbate oxidation. Binding constants and speciation of Ag+ complexes with Ctr1(1-14), which are assumed to mimic Cu+ interaction with N-terminus of Ctr1(1-14), were also determined. A preliminary immunoblot assay evidences that the anti-Ctr1 extracellular antibody recognizes Ctr1(1-14) in a different way from the longer Ctr1(1-25) that encompasses a second His and Met rich domain.

Initial rhythm control with cryoballoon ablation vs drug therapy: Impact on quality of life and symptoms.

BACKGROUND: Cryoballoon ablation (CBA) as a first-line rhythm control strategy is superior to antiarrhythmic drugs (AADs) for preventing atrial fibrillation (AF) recurrence; the impact of first-line CBA on quality of life (QoL) and symptoms has not been well characterized. METHODS: Patients aged 18 to 75 with symptomatic paroxysmal AF naïve to rhythm control therapy were randomized (1:1) to CBA (Arctic Front Advance, Medtronic) or AAD (Class I or III). Symptoms and QoL were assessed at baseline, 1, 3, 6, 9, and 12 months using the EHRA classification and Atrial Fibrillation Effect on QualiTy-of-Life (AFEQT) and SF-36v2 questionnaires. Symptomatic palpitations were evaluated via patient diary. RESULTS: Overall, 107 patients were randomized to CBA and 111 to AAD; crossovers occurred in 9%. Larger improvements in the AFEQT summary, subscale and treatment satisfaction scores were observed at 12 months with CBA vs AAD (all P <0.05). At 12 months, the mean adjusted difference in the AFEQT summary score was 9.9 points higher in the CBA group (95% CI: 5.5 -14.2, P <0.001). Clinically important improvements in the SF-36 physical and mental component scores were observed at 12 months in both groups, with no significant between group differences at this timepoint. In the CBA vs AAD group, larger improvements in EHRA class were observed at 6, 9 and 12 months (P <0.05) and the incidence rate of symptomatic palpitations was lower (4.6 vs 15.2 days/year post-blanking; IRR: 0.30, P <0.001). CONCLUSIONS: In patients with symptomatic AF, first-line CBA was superior to AAD for improving AF-specific QoL and symptoms. TRIAL REGISTRATION: ClinicalTrials.gov number: NCT01803438.

Lanthanide Identity Governs Guest-Induced Dimerization in LnIII [15-MC Cu II N(L-pheHA) -5])3+ Metallacrowns.

Series of lanthanide-containing metallic coordination complexes are frequently presented as structurally analogous, due to the similar chemical and coordinative properties of the lanthanides. In the case of chiral (LnIII [15-MC Cu II N(L-pheHA) -5])3+ metallacrowns (MCs), which are well established supramolecular hosts, the formation of dimers templated by a dicarboxylate guest (muconate) in solution of neutral pH is herein shown to have a unique dependence on the identity of the MC's central lanthanide. Calorimetric data and nuclear magnetic resonance diffusion studies demonstrate that MCs containing larger or smaller lanthanides as the central metal only form monomeric host-guest complexes whereas analogues with intermediate lanthanides (for example, Eu, Gd, Dy) participate in formation of dimeric host-guest-host compartments. The driving force for the dimerization event across the series is thought to be a competition between formation of highly stable MCs (larger lanthanides) and optimally linked bridging guests (smaller lanthanides).

Blood contains circulating cell-free respiratory competent mitochondria.

Mitochondria are considered as the power-generating units of the cell due to their key role in energy metabolism and cell signaling. However, mitochondrial components could be found in the extracellular space, as fragments or encapsulated in vesicles. In addition, this intact organelle has been recently reported to be released by platelets exclusively in specific conditions. Here, we demonstrate for the first time, that blood preparation with resting platelets, contains whole functional mitochondria in normal physiological state. Likewise, we show, that normal and tumor cultured cells are able to secrete their mitochondria. Using serial centrifugation or filtration followed by polymerase chain reaction-based methods, and Whole Genome Sequencing, we detect extracellular full-length mitochondrial DNA in particles over 0.22 µm holding specific mitochondrial membrane proteins. We identify these particles as intact cell-free mitochondria using fluorescence-activated cell sorting analysis, fluorescence microscopy, and transmission electron microscopy. Oxygen consumption analysis revealed that these mitochondria are respiratory competent. In view of previously described mitochondrial potential in intercellular transfer, this discovery could greatly widen the scope of cell-cell communication biology. Further steps should be developed to investigate the potential role of mitochondria as a signaling organelle outside the cell and to determine whether these circulating units could be relevant for early detection and prognosis of various diseases.

Cryoballoon ablation vs. antiarrhythmic drugs: first-line therapy for patients with paroxysmal atrial fibrillation.

AIMS: Treatment guidelines for patients with atrial fibrillation (AF) suggest that patients should be managed with an antiarrhythmic drug (AAD) before undergoing catheter ablation (CA). This study evaluated whether pulmonary vein isolation employing cryoballoon CA is superior to AAD therapy for the prevention of atrial arrhythmia (AA) recurrence in rhythm control naive patients with paroxysmal AF (PAF). METHODS AND RESULTS: A total of 218 treatment naive patients with symptomatic PAF were randomized (1 : 1) to cryoballoon CA (Arctic Front Advance, Medtronic) or AAD (Class I or III) and followed for 12 months. The primary endpoint was ≥1 episode of recurrent AA (AF, atrial flutter, or atrial tachycardia) >30 s after a prespecified 90-day blanking period. Secondary endpoints included the rate of serious adverse events (SAEs) and recurrence of symptomatic palpitations (evaluated via patient diaries). Freedom from AA was achieved in 82.2% of subjects in the cryoballoon arm and 67.6% of subjects in the AAD arm (HR = 0.48, P = 0.01). There were no group differences in the time-to-first (HR = 0.76, P = 0.28) or overall incidence [incidence rate ratio (IRR)=0.79, P = 0.28] of SAEs. The incidence rate of symptomatic palpitations was lower in the cryoballoon (7.61 days/year) compared with the AAD arm (18.96 days/year; IRR = 0.40, P < 0.001). CONCLUSIONS: Cryoballoon CA was superior to AAD therapy, significantly reducing AA recurrence in treatment naive patients with PAF. Additionally, cryoballoon CA was associated with lower symptom recurrence and a similar rate of SAEs compared with AAD therapy.

Comparing the Prognostic Impact of Prediabetes with Diabetes in a Nationwide Cohort of Patients with Chronic Coronary Syndromes: An Analysis of the START Registry.

AIMS: Using data from the nationwide prospective START registry that enrolled a large cohort of patients with chronic coronary syndromes (CCS), we aimed to investigate whether the presence of diabetes mellitus (DM) and pre-DM independently affected the risk of cardiovascular events at 1-year follow-up. METHODS: We assessed the impact of DM and pre-DM on all-cause mortality and a composite of all-cause mortality and hospitalization for cardiovascular causes at 1-year follow-up. RESULTS: Among the 3,778 patients with available fasting plasma glucose data at study entry, 37% were classified as DM, 25% as pre-DM, and 38% as no DM. At 1 year, patients with DM had higher rates of all-cause death (p = 0.004) and death/cardiovascular hospitalization (p = 0.003) than those with pre-DM or without DM. Conversely, no significant differences in the adverse event rate were found between patients with pre-DM and those without DM. At unadjusted Cox analysis, DM resulted as a predictor of both death for any cause (hazard ratio [HR]: 2.41; 95% confidence intervals [CI]: 1.34-4.34; p = 0.003) and all-cause death/hospitalization for cardiovascular causes (HR: 1.29; 95% CI: 1.02-1.62; p = 0.03). However, DM did not result as an independent predictor of either endpoint at multivariate analysis. CONCLUSIONS: The risk of 1-year major events among patients with CCS and pre-DM is comparable to that of patients with CCS and normoglycemic status and is lower than that of patients with DM.

Cryoablation for pulmonary veins isolation in obese patients with atrial fibrillation compared to nonobese patients.

BACKGROUND: Pulmonary veins isolation (PVI) by cryoballoon (CB) ablation is marginally represented in clinical studies in obese patients. The aim of this analysis was to evaluate the safety and efficacy of CB-PVI in a large cohort of overweight and obese patients from the 1STOP project. METHODS: From 2012 to 2018, 2048 patients with atrial fibrillation (AF) (70% male, 59 ± 11 years; 75% paroxysmal AF) underwent index CB-PVI. The patient data were separated into three cohorts for statistical evaluation, including: normal weight (body mass index [BMI] < 25 kg/m2 ), overweight (BMI = 25-30 kg/m2 ), and obese patients (BMI > 30 kg/m2 ). RESULTS: Out of 2048 patients, 693 (34%) patients had a BMI < 25 and were deemed as normal. There were 944 (46%) patients categorized as overweight (BMI = 25-30) and 411 (20%) as obese (BMI > 30). Overweight or obese patients were more often in persistent AF, had more frequently hypertension and diabetes, had higher CHA2 DS2 -VASc score, and had a number of failed antiarrhythmic drug (AAD). Periprocedural complication rates were similar among the three cohorts. The 12-month freedom from AF recurrence was 76.4% in the normal BMI group as compared to 79.2% in the overweight and 73.5% in the obese group (p = .35). However, 48% of overweight patients were on AAD treatment during the follow-up. By multivariate analysis, BMI was not a predictor for AF recurrence following the index CB-PVI. CONCLUSION: CB-PVI in obese patients is a safe procedure. Increased BMI (either moderate or severe) does not seem to be associated with a worse outcome or to a different rate of AAD discontinuation at 12 months.