Dynamic Pulmonary Vein Stenosis After Left Pneumonectomy.

Pulmonary vein stenosis might be caused by mediastinal migration into the vacated pleural space after pneumonectomy. In a patient complaining of worsening dyspnea in the left lateral decubitus position after left pneumonectomy, transthoracic echocardiography during different postures revealed pulmonary vein stenosis that worsened in the left lateral position.

Peptide-encoding gene transfer to modulate intracellular protein-protein interactions.

Peptide drug discovery has great potential, but the cell membrane is a major obstacle when the target is an intracellular protein-protein interaction (PPI). It is difficult to target PPIs with small molecules; indeed, there are no intervention tools that can target any intracellular PPI. In this study, we developed a platform that enables the introduction of peptides into cells via mRNA-based gene delivery. Peptide-length nucleic acids do not enable stable ribosome binding and exhibit little to no translation into protein. In this study, a construct was created in which the sequence encoding dihydrofolate reductase (DHFR) was placed in front of the sequence encoding the target peptide, together with a translation skipping sequence, as a sequence that meets the requirements of promoting ribosome binding and rapid decay of the translated protein. This enabled efficient translation from the mRNA encoding the target protein while preventing unnecessary protein residues. Using this construct, we showed that it can inhibit Drp1/Fis1 binding, one of the intracellular PPIs, which governs mitochondrial fission, an important aspect of mitochondrial dynamics. In addition, it was shown to inhibit pathological hyperfission, normalize mitochondrial dynamics and metabolism, and inhibit apoptosis of the mitochondrial pathway.

Endothelial CLEC-1b plays a protective role against cancer hematogenous metastasis.

Metastasis, which is the spread of cancer cells into distant organs, is a critical determinant of prognosis in patients with cancer, and blood vessels are the major route for cancer cells to spread systemically. Extravasation is a critical process for the hematogenous metastasis; however, its underlying molecular mechanisms remain poorly understood. Here, we identified that senescent ECs highly express C-type lectin domain family 1 member B (CLEC-1b), and that endothelial CLEC-1b inhibits the hematogenous metastasis of a certain type of cancer. CLEC-1b expression was enhanced in ECs isolated from aged mice, senescent cultured human ECs, and ECs of aged human. CLEC-1b overexpression in ECs prevented the disruption of endothelial integrity, and inhibited the transendothelial migration of cancer cells expressing podoplanin (PDPN), a ligand for CLEC-1b. Notably, target activation of CLEC-1b in ECs decreased the hematogenous metastasis in the lungs by cancer cells expressing PDPN in mice. Our data reveal the protective role of endothelial CLEC-1b against cancer hematogenous metastasis. Considering the high CLEC-1b expression in senescent ECs, EC senescence may play a beneficial role with respect to the cancer hematogenous metastasis.

Myofibroblasts impair myocardial impulse propagation by heterocellular connexin43 gap-junctional coupling through micropores.

Aim: Composite population of myofibroblasts (MFs) within myocardial tissue is known to alter impulse propagation, leading to arrhythmias. However, it remains unclear whether and how MFs alter their propagation patterns when contacting cardiomyocytes (CMs) without complex structural insertions in the myocardium. We attempted to unveil the effects of the one-sided, heterocellular CM-MF connection on the impulse propagation of CM monolayers without the spatial insertion of MFs as an electrical or mechanical obstacle. Methods and results: We evaluated fluo8-based spatiotemporal patterns in impulse propagation of neonatal rat CM monolayers cultured on the microporous membrane having 8-µm diameter pores with co-culture of MFs or CMs on the reverse membrane side (CM-MF model or CM-CM model, respectively). During consecutive pacing at 1 or 2 Hz, the CM monolayers exhibited forward impulse propagation from the pacing site with a slower conduction velocity (θ) and a larger coefficient of directional θ variation in the CM-MF model than that in the CM-CM model in a frequency-dependent manner (2 Hz >1 Hz). The localized placement of an MF cluster on the reverse side resulted in an abrupt segmental depression of the impulse propagation of the upper CM layer, causing a spatiotemporally non-uniform pattern. Dye transfer of the calcein loaded in the upper CM layer to the lower MF layer was attenuated by the gap-junction inhibitor heptanol. Immunocytochemistry identified definitive connexin 43 (Cx43) between the CMs and MFs in the membrane pores. MF-selective Cx43 knockdown in the MF layer improved both the velocity and uniformity of propagation in the CM monolayer. Conclusion: Heterocellular Cx43 gap junction coupling of CMs with MFs alters the spatiotemporal patterns of myocardial impulse propagation, even in the absence of spatially interjacent and mechanosensitive modulations by MFs. Moreover, MFs can promote pro-arrhythmogenic impulse propagation when in face-to-face contact with the myocardium that arises in the healing infarct border zone.

Cathepsin L prevents the accumulation of alpha-synuclein fibrils in the cell.

The deposition of α-synuclein (α-Syn) fibrils in neuronal cells has been implicated as a causative factor in Parkinson's disease (PD) and dementia with Lewy Bodies (DLB). α-Syn can be degraded by autophagy, proteasome, and chaperone-mediated autophagy, and previous studies have suggested the potency of certain cathepsins, lysosomal proteases, for α-Syn degradation. However, no studies have comprehensively evaluated all cathepsins. Here, we evaluated the efficacy of all 15 cathepsins using a cell model of α-Syn fibril propagation and found that overexpression of cathepsin L (CTSL) was the most effective in preventing the accumulation of α-Syn aggregates. CTSL-mediated degradation of α-Syn aggregates was dependent on the autophagy machinery, and CTSL itself promoted autophagy flux. Interestingly, CTSL was effective in autophagic degradation of wild-type (WT) α-Syn, but not in the case of A53T and E46K missense mutations, which are causative for familial PD. These results suggest that CTSL is a potential therapeutic strategy for sporadic PD pathology in WT α-Syn.

The importance of proinflammatory failed-repair tubular epithelia as a predictor of diabetic kidney disease progression.

The immense public health burden of diabetic kidney disease (DKD) has led to an increase in research on the pathophysiology of advanced DKD. The present study focused on the significance of proinflammatory vascular cell adhesion molecule 1 (VCAM1)+ tubules in DKD progression. A retrospective cohort study of DKD patients showed that the percentage of VCAM1+ tubules in kidney samples was correlated with poor renal outcomes. We established an advanced DKD model by partial resection of the kidneys of db/db mice and demonstrated that it closely resembled the human advanced DKD phenotype, with tissue hypoxia, tubular DNA damage, tissue inflammation, and high tubular VCAM1 expression. Luseogliflozin ameliorated tissue hypoxia and proinflammatory responses, including VCAM1+ expression, in tubules. These findings suggest the potential of tubular VCAM1 as a histological marker for poor DKD outcomes. SGLT2 inhibitors may attenuate tissue hypoxia and subsequent tissue inflammation in advanced DKD, thereby ameliorating tubular injury.

Right ventricular dilatation: echocardiographic differential diagnosis.

The initial means of detecting right ventricular (RV) dilatation is often transthoracic echocardiography (TTE), and once the presence of RV dilatation is suspected, there is the possibility of RV volume overload, RV pressure overload, RV myocardial disease, and even nonpathological RV dilatation. With respect to congenital heart disease with RV volume overload, defects or valvular abnormalities can be easily detected with TTE, with the exception of some diseases. Volumetric assessment using three-dimensional echocardiography may be useful in determining the intervention timing in these diseases. When the disease progresses in patients with pulmonary hypertension as a result of RV pressure overload, RV dilatation becomes more prominent than hypertrophy, and RV functional parameters predict the prognosis at this stage of maladaptive remodeling. The differential diagnosis of cardiomyopathy or comparison with nonpathological RV dilatation may be difficult in the setting of RV myocardial disease. The characteristics of RV functional parameters such as two-dimensional speckle tracking may help differentiate RV cardiomyopathy from other conditions. We review the diseases presenting with RV dilatation, their characteristics, and echocardiographic findings and parameters that are significant in assessing their status or intervention timing.

Oral Function and the Oral Microbiome in the Elderly in the Kyotango Area.

INTRODUCTION: Prevention of tooth loss contributes to an extended life expectancy, namely longevity. Aging-related oral hypofunction, including tooth loss, markedly increases the risks of functional disorder and mortality. Dysbiosis of the oral microbiome has recently been associated with various diseases, such as liver cirrhosis, pancreatic cancer, colorectal cancer, and inflammatory bowel disease. Therefore, the relationship between the oral microbiome and systemic health has been attracting increasing attention. In the present study, we examined oral function and the oral microbiome in the elderly in a world-leading longevity area. MATERIALS AND METHODS: An oral examination, chewing ability/tongue-lip motor function/saliva tests, and a metagenomic analysis with a 16S rRNA gene-targeting next-generation sequencer were conducted on 78 subjects aged ≥80 years. Twenty-six healthy individuals aged between 20 and 39 years were also investigated as controls. The data obtained were statistically analyzed. The protocol of the present study was approved by the Ethics Review Board of our university (ERB-C-885). RESULTS: Chewing ability, tongue-lip motor function, and saliva volume were normal in elderly subjects with a current tooth number ≥20, but were significantly lower in those with a current tooth number <20. The oral microbiome in elderly subjects with a current tooth number ≥20 and young controls differed from that in elderly subjects with a current tooth number <20. CONCLUSION: Tooth number ≥20 in elderly subjects in the longevity area contributed to the maintenance of both oral function and the diversity of the oral microbiome.

The Cavin-1/Caveolin-1 interaction attenuates BMP/Smad signaling in pulmonary hypertension by interfering with BMPR2/Caveolin-1 binding.

Caveolin-1 (CAV1) and Cavin-1 are components of caveolae, both of which interact with and influence the composition and stabilization of caveolae. CAV1 is associated with pulmonary arterial hypertension (PAH). Bone morphogenetic protein (BMP) type 2 receptor (BMPR2) is localized in caveolae associated with CAV1 and is commonly mutated in PAH. Here, we show that BMP/Smad signaling is suppressed in pulmonary microvascular endothelial cells of CAV1 knockout mice. Moreover, hypoxia enhances the CAV1/Cavin-1 interaction but attenuates the CAV1/BMPR2 interaction and BMPR2 membrane localization in pulmonary artery endothelial cells (PAECs). Both Cavin-1 and BMPR2 are associated with the CAV1 scaffolding domain. Cavin-1 decreases BMPR2 membrane localization by inhibiting the interaction of BMPR2 with CAV1 and reduces Smad signal transduction in PAECs. Furthermore, Cavin-1 knockdown is resistant to CAV1-induced pulmonary hypertension in vivo. We demonstrate that the Cavin-1/Caveolin-1 interaction attenuates BMP/Smad signaling and is a promising target for the treatment of PAH.

Impact of Sleep Apnea on Nocturnal Parasympathetic Activity in Atrial Fibrillation Patients After Catheter Ablation　- Implications for Heart Rate Variability Analysis.

BACKGROUND: The impact of sleep apnea (SA) on heart rate variability (HRV) in atrial fibrillation (AF) patients has not been investigated.Methods and Results: Of 94 patients who underwent AF ablation between January 2021 and September 2022, 76 patients who had a nocturnal Holter electrocardiography and polysomnography conducted simultaneously were included in the analysis. A 15-min duration of HRV, as determined by an electrocardiogram during apnea and non-apnea time, were compared between patients with and without AF recurrence at 12 months' postoperatively. Patients had a mean age of 63.4±11.6 years, 14 were female, and 20 had AF recurrence at 12 months' follow-up. The root mean square of the difference between consecutive normal-to-normal intervals (RMSSD, ms) an indicator of a parasympathetic nervous system, was more highly increased in patients with AF recurrence than those without, during both apnea and non-apnea time (apnea time: 16.7±4.5 vs. 13.5±3.3, P=0.03; non-apnea time: 20.9±9.5 vs. 15.5±5.9, P<0.01). However, RMSSD during an apneic state was decreased more than that in a non-apneic state in both groups of patients with and without AF recurrence (AF recurrence group: 16.7±4.5 vs. 20.9±9.5, P<0.01; non-AF recurrence group; 13.5±3.3 vs. 15.5±5.9, P=0.03). Consequently, the effect of AF recurrence on parasympathetic activity was offset by SA. Similar trends were observed for other parasympathetic activity indices; high frequency (HF), logarithm of HF (lnHF) and the percentage of normal-to-normal intervals >50 ms (pNN50). CONCLUSIONS: Without considering the influence of SA, the results of nocturnal HRV analysis might be misinterpreted. Caution should be taken when using nocturnal HRV as a predictor of AF recurrence.

Cavin-2 promotes fibroblast-to-myofibroblast trans-differentiation and aggravates cardiac fibrosis.

AIMS: Transforming growth factor ß (TGF-ß) signalling is one of the critical pathways in fibroblast activation, and several drugs targeting the TGF-ß/Smad signalling pathway in heart failure with cardiac fibrosis are being tested in clinical trials. Some caveolins and cavins, which are components of caveolae on the plasma membrane, are known for their association with the regulation of TGF-ß signalling. Cavin-2 is particularly abundant in fibroblasts; however, the detailed association between Cavin-2 and cardiac fibrosis is still unclear. We tried to clarify the involvement and role of Cavin-2 in fibroblasts and cardiac fibrosis. METHODS AND RESULTS: To clarify the role of Cavin-2 in cardiac fibrosis, we performed transverse aortic constriction (TAC) operations on four types of mice: wild-type (WT), Cavin-2 null (Cavin-2 KO), Cavin-2flox/flox , and activated fibroblast-specific Cavin-2 conditional knockout (Postn-Cre/Cavin-2flox/flox , Cavin-2 cKO) mice. We collected mouse embryonic fibroblasts (MEFs) from WT and Cavin-2 KO mice and investigated the effect of Cavin-2 in fibroblast trans-differentiation into myofibroblasts and associated TGF-ß signalling. Four weeks after TAC, cardiac fibrotic areas in both the Cavin-2 KO and the Cavin-2 cKO mice were significantly decreased compared with each control group (WT 8.04 ± 1.58% vs. Cavin-2 KO 0.40 ± 0.03%, P < 0.01; Cavin-2flox/flox , 7.19 ± 0.50% vs. Cavin-2 cKO 0.88 ± 0.44%, P < 0.01). Fibrosis-associated mRNA expression (Col1a1, Ctgf, and Col3) was significantly attenuated in the Cavin-2 KO mice after TAC. α1 type I collagen deposition and non-vascular αSMA-positive cells (WT 43.5 ± 2.4% vs. Cavin-2 KO 25.4 ± 3.2%, P < 0.01) were reduced in the heart of the Cavin-2 cKO mice after TAC operation. The levels of αSMA protein (0.36-fold, P < 0.05) and fibrosis-associated mRNA expression (Col1a1, 0.69-fold, P < 0.01; Ctgf, 0.27-fold, P < 0.01; Col3, 0.60-fold, P < 0.01) were decreased in the Cavin-2 KO MEFs compared with the WT MEFs. On the other hand, αSMA protein levels were higher in the Cavin-2 overexpressed MEFs compared with the control MEFs (2.40-fold, P < 0.01). TGF-ß1-induced Smad2 phosphorylation was attenuated in the Cavin-2 KO MEFs compared with WT MEFs (0.60-fold, P < 0.01). Heat shock protein 90 protein levels were significantly reduced in the Cavin-2 KO MEFs compared with the WT MEFs (0.69-fold, P < 0.01). CONCLUSIONS: Cavin-2 loss suppressed fibroblast trans-differentiation into myofibroblasts through the TGF-ß/Smad signalling. The loss of Cavin-2 in cardiac fibroblasts suppresses cardiac fibrosis and may maintain cardiac function.

Cost-effective analysis of transcatheter aortic valve replacement in patients with severe symptomatic aortic stenosis: A prospective multicenter study.

BACKGROUND: Transcatheter aortic valve replacement (TAVR) for severe symptomatic aortic stenosis (AS) does not benefit all patients. We performed a prospective multicenter study to investigate the cost-effectiveness of TAVR in a Japanese cohort. METHODS AND RESULTS: We prospectively enrolled 110 symptomatic patients with severe AS who underwent TAVR from five institutions. The quality of life measurement (QOL) was performed for each patient before and at 6 months after TAVR. Patients without an improvement in QOL at 6 months after TAVR were defined as non-responders. Pre-TAVR higher QOL, higher clinical frailty scale predicted the non-responders. Three models, 1) conservative treatment for all patients strategy, 2) TAVR for all patients strategy, and 3) TAVR for a selected patient strategy who is expected to be a responder, were simulated. Lifetime cost-effectiveness was estimated using incremental cost-effectiveness ratio (ICER) and cost per quality-adjusted life-year (QALY) gained. In comparison to conservative therapy for all patients, ICER was estimated to be 5,765,800 yen/QALY for TAVR for all patients and 2,342,175 yen/QALY for TAVR for selected patient strategy patients, which is less than the commonly accepted ICER threshold of 5,000,000 yen/QALY. CONCLUSIONS: TAVR for selected patient strategy model is more cost-effective than TAVR for all patient strategy without reducing QOL in the Japanese healthcare system. TAVR for selected patient strategy has potential benefit for optimizing the TAVR treatment in patients with high frailty and may direct our resources toward beneficial interventions.

Mitral regurgitation outcomes after transcatheter atrial septal defect closure.

BACKGROUND: Worsening mitral regurgitation (MR) is a complication of intervention for atrial septal defect (ASD). Little is known about mitral valve (MV) characteristics associated with worsening MR. We aimed to elucidate MR outcomes and predictors of worsening MR after transcatheter ASD closure. METHODS: We analyzed changes in MR from prior to transcatheter ASD closure to 6 months after the procedure and predictors of worsening MR via baseline transthoracic echocardiography in 238 patients (64.7% females; mean age, 53 ± 22 years). RESULTS: Worsening MR was defined as worsening to moderate in patients with less than or equal to mild MR at baseline or vena contracta width increasing of ≥2 mm by 6-month follow-up in patients with moderate MR. Worsening MR was observed in 29 patients (12.2%). The associated echocardiographic findings were pseudoprolapse, hamstringing, stiffness, and anteroposterior and intercommissural mitral annulus diameter in the univariable logistic regression analysis (all P < 0.05). Multivariable analysis after adjusting for age; long-standing persistent atrial fibrillation; and ASD size showed that models combining MV leaflet findings such as pseudoprolapse or hamstringing, or anterior leaflet stiffness with the ratio of the sum of anterior and posterior leaflet lengths to intercommissural mitral annulus diameter were statistically significant for predicting worsening MR (R2 = 0.393, P < 0.001 and R2 = 0.385, P < 0.001, respectively). CONCLUSIONS: Worsening MR after transcatheter ASD closure might depend on MV leaflet findings and annulus size in patients with long-standing persistent atrial fibrillation.

Generation of inducible mitophagy mice.

Mitophagy is programmed selective autophagy of mitochondria and is important for mitochondrial quality control and cellular homeostasis. Mitochondrial dysfunction and impaired mitophagy are closely associated with various diseases, including heart failure and diabetes. To better understand the pathophysiological role of mitophagy, we generated doxycycline-inducible mitophagy mice using a synthetic mitophagy adaptor protein consisting of an outer mitochondrial membrane targeting sequence and an engineered LIR. To evaluate the activation of mitophagy upon doxycycline treatment, we also generated mitophagy reporter mito-QC mice in which mitochondria tandemly express mCherry and GFP, and only GFP signals are lost in acidic lysosomes subjected to mitophagy. With the ROSA26 promoter-driven rtTA, mitophagy was observed at least in heart, liver, and skeletal muscle. We investigated the relationship between mitophagy activation and pressure overload heart failure or high fat diet-induced obesity. Unexpectedly, we were unable to confirm the protective effect of mitophagy in these two pathological models. Further titration of the level of mitophagy induction is required to demonstrate the potency of the protective effects of mitophagy in disease models.

Jugular Venous Pressure and Kussmaul's Sign as Predictors of Outcome in Heart Failure.

Simplifying the estimation of internal jugular venous pressure (JVP) as visible or not visible above the right clavicle in the sitting position has attracted attention for risk assessment in patients with heart failure (HF). It remains unclear whether this simple assessment, combined with its inspiration response known as Kussmaul's sign, is useful in patients with HF who vary in features such as HF with reduced ejection fraction (HFrEF) and preserved ejection fraction (HFpEF).This study consisted of 246 patients who were admitted for the management of HF. JVP was assessed before discharge and considered high if visible at rest. The inspiration response was also examined. The primary outcome was a composite of all-cause death and hospitalization for worsening HF.One year after discharge, primary outcome events occurred in 91 patients (37%). The incidence of primary outcome was higher in patients with a high JVP at rest (odds ratio, 5.06; 95% confidence interval, 2.31-11.1; P = 0.0001) or with inspiration (odds ratio, 5.93; 95% confidence interval, 2.14-16.4; P < 0.01) than in patients without high JVP conditions. These findings were similarly observed among patients with HFrEF and HFpEF (odds ratios, 3.53 and 6.76; 95% confidence intervals, 1.68-8.68 and 2.19-15.5; P = 0.01 and < 0.01, respectively) and in subgroup analysis stratified by baseline characteristics of the patients.A high JVP at rest and with inspiration as assessed by this simple, practical method may be useful for risk assessment in patients with HF, independent of baseline characteristics.