Prebiotic effect of poly-D-3-hydroxybutyrate prevents dyslipidemia in obese mice

Obesity is a global health problem caused by genetic, environmental, and psychological factors and is associated with various health disorders. As such, there is a growing focus on the prevention of obesity and related diseases. The gut microbiota plays a crucial role in these diseases and has become a therapeutic target. Prebiotics, such as poly-d-3-hydroxybutyric acid (PHB), have gained attention for their potential to alter the gut microbiota, promote beneficial bacterial growth, and alleviate obesity. In this study, we examined the prebiotic effects of PHB in obese mice. We found that, in C57BL/6N mice, PHB reduced blood lipid levels. Analysis of the intestinal microflora also revealed an increase in short-chain fatty acid-producing bacteria. When PHB was administered to obese mice, subcutaneous fat and dyslipidemia were reduced, and the number of beneficial bacteria in the intestinal microflora increased. Furthermore, fatty degradation and oxidative stress were suppressed in the liver. PHB regulates gut bacterial changes related to obesity and effectively inhibits dyslipidemia, suggesting that it could be a prebiotic agent for curing various obesity-related diseases. In summary, PHB increases the beneficial gut microbiota, leading to an alleviation of obesity-associated dyslipidemia.

Pharmacokinetic Analysis of Zonarol, a Marine Algal Hydroquinone, in Mice Using HPLC with Fluorescence Detection

Zonarol, which was discovered in the brown algae Dictyopteris undulata, has antibiotic, antioxidative, anti-inflammatory, and neuroprotective hydroquinone properties. Additionally, a daily treatment of zonarol taken orally has been proven to prevent ulcerative colitis and nonalcoholic fatty liver disease in experimentally induced mice models. In this study, to elucidate the physiological behavior of zonarol in vivo, the establishment of quantitative methods for the determination of zonarol in biological samples and basic pharmacokinetics parameters after oral or intravenous administration with purified zonarol to mice were investigated. The zonarol (20-600 ng/mL) in this study was dose-dependently detected using an HPLC-FI system as a single peak on the ODS column with 80% aqueous methanol at 332 nm with an excitation of 293 nm. The pharmacokinetic parameters were derived from a non-compartment analysis of the plasma concentration of zonarol following oral or intravenous treatment in mice. The absolute bioavailability of zonarol was calculated as 25.0%. Interestingly, the maximal distribution of zonarol in the brain (2.525 ± 1.334 µg/g tissue) at 30 min was observed to be higher and slower than that in the liver and kidney at 15 min after bolus intravenous administrations to the mice (10 mg/kg BW). Based on these results, zonarol might be a candidate for a potential drug, an effective tool for drug delivery, or enhancing the treatment of cerebral disease.

New prebiotics by ketone donation

Integrity of the microbiome is an essential element for human gut health. 3-Hydroxybutyrate (3HB) secreted into the gut lumen has gained attention as a regulator of gut physiology, including stem cell expansion. In this opinion, I propose new prebiotics leading to gut health by use of a ketone (3HB) donor. When exogenous 3HB is supplied through ketone donation, it has the potential to markedly improve gut health by altering the gut microbiome and systemic metabolic status. Poly-hydroxybutyrate (PHB) donates 3HB and primarily influences microbiota, making it an effective prebiotic for improving the gut environment. Thus, exogenous 3HB donation to the lumen of the gut may aid gut health by maintaining the integrity of microbiome.

Characterization of the surugamide biosynthetic gene cluster of TUA-NKU25, a Streptomyces diastaticus strain isolated from Kusaya, and its effects on salt-dependent growth

Kusaya, a traditional Japanese fermented fish product, is known for its high preservability, as it contains natural antibiotics derived from microorganisms, and therefore molds and yeasts do not colonize it easily. In this study, the Streptomyces diastaticus strain TUA-NKU25 was isolated from Kusaya, and its growth as well as the production of antibiotics were investigated. Strain TUA-NKU25 showed advantageous growth characteristics in the presence, but not in the absence, of sodium chloride (NaCl). Antimicrobial assay, high-performance liquid chromatography, and electrospray ionization-mass spectrometry analysis showed that this strain produced surugamide A and uncharacterized antimicrobial compound(s) during growth in the presence of NaCl, suggesting that the biosynthesis of these compounds was upregulated by NaCl. Draft genomic analysis revealed that strain TUA-NKU25 possesses a surugamide biosynthetic gene cluster (sur BGC), although it is incomplete, lacking surB/surC. Phylogenetic analysis of strain TUA-NKU25 and surugamide-producing Streptomyces showed that sur BGC formed a clade distinct from other known groups.

The novel sustained 3-hydroxybutyrate donor poly-D-3-hydroxybutyric acid prevents inflammatory bowel disease through upregulation of regulatory T-cells

Inflammatory bowel disease (IBD) is a chronic persistent intestinal disorder, with ulcerative colitis and Crohn's disease being the most common. However, the physio-pathological development of IBD is still unknown. Therefore, research on the etiology and treatment of IBD has been conducted using a variety of approaches. Short-chain fatty acids such as 3-hydroxybutyrate (3-HB) are known to have various physiological activities. In particular, the production of 3-HB by the intestinal microflora is associated with the suppression of various inflammatory diseases. In this study, we investigated whether poly-D-3-hydroxybutyric acid (PHB), a polyester of 3-HB, is degraded by intestinal microbiota and works as a slow-release agent of 3-HB. Further, we examined whether PHB suppresses the pathogenesis of IBD models. As long as a PHB diet increased 3-HB concentrations in the feces and blood, PHB suppressed weight loss and histological inflammation in a dextran sulfate sodium-induced IBD model. Furthermore, PHB increased the accumulation of regulatory T cells in the rectum without affecting T cells in the spleen. These results indicate that PHB has potential applications in treating diseases related to the intestinal microbiota as a sustained 3-HB donor. We show for the first time that biodegradable polyester exhibits intestinal bacteria-mediated bioactivity toward IBD. The use of bioplastics, which are essential materials for sustainable social development, represents a novel approach to diseases related to dysbiosis, including IBD.

A phase II trial of stereotactic body radiotherapy in 4 fractions for patients with localized prostate cancer

Purpose/objective(s)

To report results from our phase II study of stereotactic body radiotherapy (SBRT) delivering 36 Gy in 4 fractions for patients with localized prostate cancer.

Materials/methods

We enrolled 55 patients treated with SBRT delivering 36 Gy in 4 fractions between 2015 to 2018. All patients were categorized as low-risk (n = 4), intermediate-risk (n = 31) or high-risk (n = 20) according to National Comprehensive Cancer Network criteria. Median age was 73 years (range 54–86 years). Two-thirds of patients (n = 37) had received androgen-deprivation therapy for 3–46 months (median, 31 months). Median duration of follow-up was 36 months (range 1–54 months). We used Radiation Therapy Oncology Group and National Cancer Institute—Common Toxicity Criteria version 4 for toxicity assessments. Quality of life (QOL) outcomes were also evaluated using the Expanded Prostate Cancer Index Composite (EPIC).

Results

Protocol treatments were completed for all patients. Six patients experienced biochemical failures. Among these six patients, three patients experienced clinical failure. One patient showed bone metastasis before biochemical failure. One patient died of gastric cancer. The 3-year biochemical control rate was 89.8%. Acute grade 2 genitourinary (GU) and gastrointestinal (GI) toxicities were observed in 5 patients (9%) and 6 patients (11%), respectively. No grade 3 or higher acute toxicities were observed. Late grade 2 GU and GI toxicities were observed in 7 patients (13%) and 4 patients (7%), respectively. Late grade 3 GU and GI toxicities were observed in 1 patient (1.8%) each. EPIC scores decreased slightly during the acute phase and recovered within 3 months after treatment.

Conclusion

Our phase II study showed that SBRT delivering 36 Gy in 4 fractions was safe and effective with favorable QOL outcomes, although this regimen showed slightly more severe toxicities compared to current standards.

Bird evolution by insulin resistance

Drift of oxygen concentrations in the atmosphere was one of the main drivers of the evolution of vertebrates. The drop in oxygen concentrations at the Permian-Triassic (PT) boundary may have been the biggest challenge to vertebrates. This hypoxic condition forced theropods to lose certain genes to maximize their efficiency of oxygen usage. Recent studies show that omentin and insulin-sensitive glucose transporter 4 (GLUT4) are missing in the bird genome. Since these gene products play essential roles in maintaining insulin sensitivity, this loss forced theropods to become insulin resistant. Insulin resistance may have been the key to allowing theropods to become hyperathletic under hypoxic conditions and to outcompete mammals during the Triassic period. A second challenge was the gradual increase in oxygen concentrations during the late Jurassic, Cretaceous, and Tertiary periods when reactive oxygen species (ROS) leakage from mitochondria became a problem. Since the simplest solution was the expansion of body size, some theropods became bigger to reduce ROS leakage per volume. Another solution was the development of a constitutively active countermeasure against ROS. A recent study shows that Neoaves have constitutively active nuclear factor erythroid 2-related factor 2 (NRF2) due to deletion of the C-terminal part of the KEAP1 protein, thus allowing Neoaves to express antioxidant enzymes to overcome ROS leakage.

Zonarol Protected Liver from Methionine- and Choline-Deficient Diet-Induced Nonalcoholic Fatty Liver Disease in a Mouse Model

Nonalcoholic fatty liver disease (NAFLD) is one of the most common liver diseases with no approved treatment. Zonarol, an extract from brown algae, has been proven to have anti-inflammatory and antioxidant effects. In this study, we investigated the role of zonarol in the progression of methionine- and choline-deficiency (MCD) diet-induced NAFLD in mice. After oral treatment with zonarol, a lighter body weight was observed in zonarol group (ZG) mice in comparison to control group (CG) mice. The NAFLD scores of ZG mice were lower than those of CG mice. Hepatic and serum lipid levels were also lower in ZG mice with the reduced expression of lipid metabolism-related factors. Furthermore, ZG mice showed less lipid deposition, less inflammatory cell infiltration and lower inflammatory cytokine levels in comparison to CG mice. Moreover, the numbers of 8-hydroxy-20-deoxyguanosine (8-OHdG)-positive hepatocytes and levels of hepatic and serum thiobarbituric acid reactive substances (TBARS) were significantly lower in comparison to CG mice. The expression levels of nuclear factor erythroid 2 related factor 2 (Nrf2), as well as its upstream and downstream molecules, changed in ZG mice. Zonarol could prevent the progression of NAFLD by decreasing inflammatory responses, oxidative stress and improving lipid metabolism. Meanwhile the Nrf2 pathway may play an important role in these effects.

Ultrafast Amplification and Nonlinear Magnetoelastic Coupling of Coherent Magnon Modes in an Antiferromagnet

We investigate the role of domain walls in the ultrafast magnon dynamics of an antiferromagnetic NiO single crystal in a pump-probe experiment with variable pump photon energy. Analyzing the amplitude of the energy-dependent photoinduced ultrafast spin dynamics, we detect a yet unreported coupling between the material's characteristic terahertz- and gigahertz-magnon modes. We explain this unexpected coupling between two orthogonal eigenstates of the corresponding Hamiltonian by modeling the magnetoelastic interaction between spins in different domains. We find that such interaction, in the nonlinear regime, couples the two different magnon modes via the domain walls and it can be optically exploited via the exciton-magnon resonance.

AB0045 THE RELATIONSHIP BETWEEN CD14 AND VIMENTIN-POSITIVE SYNOVIAL DENDRITIC-SHAPED CELLS AND SYNOVITIS IN RHEUMATOID ARTHRITIS

Background:

Inflammation in rheumatoid arthritis (RA) is caused by multiple cell types, including infiltrating inflammatory cells, such as lymphocytes, neutrophils, macrophages, and spindle-shaped fibroblasts. Especially, we are focusing on fibroblast-like synoviocytes (FLSs). In our previous study, we have reported that FLSs were positive for multiple markers including CD14, CD68 and HLA-DR, and were dendritic-shaped cells constituting nursing phenomenon between lymph or plasma cells. In addition, in our recent study, we found that CD14+FLSs were positive for vimentin (VIM), which is a marker for mesenchymal cells. There are still many issues to be discussed regarding CD14+VIM+ cells.

Objectives:

To investigate the relationship between CD14+VIM+ cells and the degree of synovitis in rheumatoid arthritis.

Methods:

Synovial tissues collected from RA patients who underwent joint surgeries were prepared for this study. First, the proportions of CD14+ cells in RA synovial tissue and control were analyzed using flow cytometry and the concentrations of inflammatory cytokines released by CD14+ cells in RA synovial tissue and control were examined by ELISA. Next, the proportions of CD14+VIM+ cells in RA synovial tissue and control were examined immunohistologically and then we analyzed the results using image analysis software. Also, we statistically analyzed the relationship between the proportion of CD14+VIM+ cells, the degree of synovitis, and clinical data.

Results:

Results of flow cytometry showed that CD14+ cells were frequently observed in RA synovial tissue than control. Cultured CD14+ cells released more inflammatory cytokines than cultured CD14- cells. Also, results of immunohistological staining showed that many CD14+VIM+ cells were observed in RA synovial tissue than in control. The proportion of CD14+VIM+ cells was correlated with Krenn synovitis score. High proportion cases significantly showed high level of CRP and MMP-3.

Conclusion:

CD14+VIM+ cells might be involved in the mechanism of chronic immunological inflammation in RA and the proportion of these cells might influence the clinical data.

References:

[1]Ochi T, Yoshikawa H, Toyosaki-Maeda T, Lipsky PE. Mesenchymal stromal cells. Nurse-like cells reside in thesynovial tissue and bone marrow in rheumatoid arthritis. Arthritis Research&Therapy 2007; 9(1): 201.

[2]Ochi T, Sawai T, Murakami K, Kamataki A, Uzuki M, Tomita T, et al. Nurse-like cells in rheumatoid arthritis: Formation of survival niches cooperating between the cell types. Mod Rheum 2018; 29: 1-5.

[3]Krenn V, Morawietz L, Burmester GR, Kinne RW, Muller-Ladner U, Muller B, Haupl T. Synovitis score: discrimination between chronic low-grade and high-grade synovitis. Histopathology 2006; 49: 358-64.

Disclosure of Interests:

None declared

Efficacy and safety of abiraterone acetate plus prednisolone in patients with early metastatic castration-resistant prostate cancer who failed first-line androgen-deprivation therapy: a single-arm, phase 4 study

Aim

The aim was to evaluate the efficacy and safety of abiraterone acetate plus prednisolone in patients with chemotherapy-naïve early metastatic castration-resistant prostate cancer who failed first-line androgen deprivation therapy.

Methods

Patients with early metastatic castration-resistant prostate cancer with confirmed prostate-specific antigen progression within 1-year or prostate-specific antigen progression without having normal prostate-specific antigen level (<4.0 ng/mL) during first-line androgen deprivation therapy were enrolled and administered abiraterone acetate (1000 mg) plus prednisolone (10 mg). A minimum of 48 patients were required according to Simon’s minimax design. The primary endpoint was prostate-specific antigen response rate (≥50% prostate-specific antigen decline by 12 weeks), secondary endpoints included prostate-specific antigen progression-free survival and overall survival. Safety parameters were also assessed.

Results

For efficacy, 49/50 patients were evaluable. Median age was 73 (range: 55–86) years. The median duration of initial androgen deprivation therapy was 32.4 (range: 13.4–84.1) weeks and 48 patients experienced prostate-specific antigen progression within 1-year after initiation of androgen deprivation therapy. prostate-specific antigen response rate was 55.1% (95% confidence interval: 40.2%–69.3%), median prostate-specific antigen–progression-free survival was 24.1 weeks, and median overall survival was 102.9 weeks (95% confidence interval: 64.86 not estimable [NE]). Most common adverse event was nasopharyngitis (15/50 patients, 30.0%). The most common ≥grade 3 adverse event was alanine aminotransferase increased (6/50 patients, 12.0%).

Conclusions

Abiraterone acetate plus prednisolone demonstrated a high prostate-specific antigen response rate of 55.1%, suggesting tumor growth still depends on androgen synthesis in patients with early metastatic castration-resistant prostate cancer. However, prostate-specific antigen–progression-free survival was shorter than that reported in previous studies. Considering the benefit–risk profile, abiraterone acetate plus prednisolone would be a beneficial treatment option for patients with chemotherapy-naive metastatic prostate cancer who show early castration resistance.

Brightness modulations of our nearest terrestrial planet Venus reveal atmospheric super-rotation rather than surface features

Terrestrial exoplanets orbiting within or near their host stars’ habitable zone are potentially apt for life. It has been proposed that time-series measurements of reflected starlight from such planets will reveal their rotational period, main surface features and some atmospheric information. From imagery obtained with the Akatsuki spacecraft, here we show that Venus’ brightness at 283, 365, and 2020 nm is modulated by one or both of two periods of 3.7 and 4.6 days, and typical amplitudes  <10% but occasional events of 20–40%. The modulations are unrelated to the solid-body rotation; they are caused by planetary-scale waves superimposed on the super-rotating winds. Here we propose that two modulation periods whose ratio of large-to-small values is not an integer number imply the existence of an atmosphere if detected at an exoplanet, but it remains ambiguous whether the atmosphere is optically thin or thick, as for Earth or Venus respectively. Multi-wavelength and long temporal baseline observations may be required to decide between these scenarios. Ultimately, Venus represents a false positive for interpretations of brightness modulations of terrestrial exoplanets in terms of surface features.

Establishing diagnostics for terrestrial exoplanets are crucial for their characterization. Here, the authors show brightness modulations of Venus are caused by planetary-scale waves superimposed on the super-rotating winds can be used to detect existence of an atmosphere if detected at an exoplanet.

Metabolic syndrome contributes to the pulmonary arterial dysfunction in pulmonary hypertension in heart failure with preserved ejection fraction

Background

Many Heart Failure with preserved Ejection Fraction (HFpEF) patients have metabolic syndrome and develop Exercise Induced Pulmonary Hypertension (EIPH). The pathogenesis of EIPH in HFpEF remains unclear as there is no rodent model. As the SGLT2 inhibitor Empagliflozin improves clinical outcome in patients with type 2 diabetes and cardiovascular risk, we tested its effect on EIPH in a novel rat model of HFpEF.

Methods

Obese ZSF1 (HFpEF model) with leptin receptor mutation have metabolic syndrome and received the VEGF-inhibitor SU5416 to stimulate PH (Obese + Sugen). Half also received Empagliflozin (0.2 mg/kg/day) in drinking water from 8 to 22 weeks old. Lean ZSF1 lacking the mutation served as controls. During treadmill exercise, right/left ventricle (RV/LV) hemodynamics were evaluated via catheters. Pulmonary artery vascular smooth muscle cells (PAVSMC) prepared from normal or diabetic patients were cultured in standard media, or with Palmitate acid, Glucose and Insulin (PGI) to induce metabolic stress. Flow cytometry was used to evaluate reactive oxygen species (ROS) in mitochondria (Mitosox) or cytoplasm (CellROX).

Results

Relative to Lean, Obese + Sugen had increased body weight and HgA1C (Fig. 1A). Relative to Lean and at rest, Obese + Sugen showed mildly elevated RVSP and LVEDP. After exercise, LVSP and LVEDP rose similarly in Lean and Obese + Sugen. However, after exercise, Obese + Sugen showed a markedly greater increase in RVSP and exercise intolerance consistent with EIPH (Fig. 1B). In MR imaging of PA, Lean showed dobutamine (5 μg/kg/min)-induced PA dilation, which was not seen in Obese + Sugen (Fig. 1C). Protein levels of sGCβ1 (key regulator of PA relaxation) and its transcription factor (NFYA) both were decreased in PA from Obese + Sugen relative to Lean (Fig. 1D). Obese + Sugen + SGLT2 inhibitor treated rats showed marked improvements metabolic syndrome (body weight, HgA1c), exercise induced increase in RVSP, PA response to dobutamine, and increased NFYA and sGCβ1 expression (Fig. 1A–D). We observed greater ROS-induced DNA damage (8-OHdG staining) (Fig. 1E) and mitochondrial complex I, III, and IV activity in Obese + Sugen PA that was normalized in Obese + Sugen + SGLT2 inhibitor (Fig. 1F), suggesting a role of ROS in EIPH. Control human PAVSMC treated with PGI media showed elevated cytoplasmic and mitochondrial ROS, associated with increased mitochondrial complex I, III, IV and V activity (Fig. 1F, G). PGI media also accelerated the degradation of NFYA RNA and protein level in a manner mimicked by H2O2, and prevented by catalase/SOD (Fig. 1H, I), suggesting PGI-induced ROS enhanced NFYA degradation. Diabetic human PAVSMCs cultured in normal media resembled PGI-treated normal cells with respect to sGCb1 and NFYA expression, and in response to catalase/SOD (Fig. 1H, I).

Conclusions

In this PH-HFpEF model, metabolic syndrome contributes to PA dysfunction and EIPH through mitochondrial dysfunction and enhanced ROS, which were improved by Empagliflozin treatment.

Figure 1

Funding Acknowledgement

Type of funding source: None

Leg raise can detect exercise-induced pulmonary arterial wedge pressure elevation

Background

Exercise-induced elevation of pulmonary arterial wedge pressure (PAWP) may show preclinical or exercise-induced left ventricular diastolic dysfunction. Invasive hemodynamic assessment during provocative maneuvers, like exercise and volume challenge, in these patients allows greater sensitivity to diagnose or exclude HFpEF. The aim of this study was to examine how the leg raise, which is a simple way to increase preload, can detect exercise-induced PAWP elevation.

Methods

Four hundred seventy-nine patients (60±14y.o, mean pulmonary arterial pressure (PAP) 19mmHg, PAWP 8mmHg, CTEPH /IPAH/CTD-PH/SOB unknown reason: 357/56/38/28pts) with near-normal PAP and normal PAWP at rest underwent symptom-limited exercise test using supine cycle ergometer with right heart catheter. Exercise-induced elevation in PAWP of over 20mmHg was defined as exercise-induced elevation group.

Results

ΔPAWP (after leg raise - rest) in the exercise-induced elevation group was significantly higher (6.0±4.1 vs. 2.7±3.9mmHg, p&lt;0.001, in the older (age≥60y.o) group (n=276); 3.4±3.5 vs. 1.9±3.4mmHg, p&lt;0.001, in the younger (age&lt;60y.o) group (n=203)) than that in the non-elevation group after legs raise for cycle ergometer exercise. The area under the ROC curve for ΔPAWP was 0.72 (95% CI: 0.65–0.78) in the older and 0.64 (95% CI: 0.53–0.75) in the younger. In the older, the cut-off value for detect exercise-induced PAWP elevation of ΔPAWP was 4mmHg, with 72% sensitivity and 58% specificity. On the other hand, in the younger, the cut-off value was 3mmHg, with 69% sensitivity and 59% specificity.

Conclusion

Leg raise can easily detect occult left ventricular diastolic dysfunction.

Funding Acknowledgement

Type of funding source: None

Comparison of pulmonary vascular resistance and pulmonary artery compliance during exercise between IPAH and CTEPH with normal pulmonary artery pressure

Background

Pulmonary vascular resistance (PVR) and pulmonary artery compliance (PAC) are inversely related. However, the little is known about dynamics during exercise by disease difference. The aim of this study was to reveal the relationships of PVR and PAC during exercise between idiopathic pulmonary arterial hypertension (IPAH) and chronic thromboembolic pulmonary hypertension (CTEPH) patients.

Methods

Sixty-two IPAH patients (45±9 y.o) and 359 CTEPH patients (63±13 y.o) with normal mean PAP and PAWP at rest underwent symptom-limited exercise test using supine cycle ergometer with right heart catheter.

Results

There were no differences between baseline mean PAP and PAWP in 2 groups, however, cardiac output, SaO2 and SvO2 were lower in CTEPH group. Lower PAC (2.9±1.1 vs. 3.7±1.7 ml/mmHg, p&lt;0.001) and higher PVR (2.3±1.0 vs. 1.9±1.0 wood.unit, p=0.016) were observed in CTEPH group. These trends were also seen at peak exercise. PVR-PAC relationship in CTEPH group was leftward shift compared with IPAH group (Figure 1).

Conclusion

Resting and exercise PVR and PAC in CTEPH patients were worse than those in IPAH patients who had normal PAP and PAWP at rest.

Figure 1

Funding Acknowledgement

Type of funding source: None

Novel risk factor for fatal arrhythmia in Brugada syndrome

Background

Brugada syndrome (BrS) is a genetic disease associated with increased risk of ventricular fibrillation (VF)/ventricular tachycardia (VT). The VF/VT in BrS occurs more frequently during a night time or at a rest with parasympathetic nerve activation. Some risk factors of VF/VT occurrence in BrS have been elucidated, however, it remains controversial about risk stratification. Salusin-β is an endogenous bioactive peptide that systemically exerts rapid and profound hypotensive and bradycardic activities and parasympathomimetic hemodynamic actions in vivo. Previous reports suggested that salusin-β is suppressed following physiological parasympathetic stimulation and appears to constitute a negative feedback relationship with the parasympathetic nervous system.

Purpose

We hypothesized that salusin-β is associated with the occurrence of VF/VT in BrS.

Methods

The study population consisted of 26 BrS patients with newly implantation of implantable cardioverter defibrillator (ICD) during 2003–2008. In all patients, salusin-β was measured in supine position after 20 minute rest. The date of salusin-β sampling was set as the registration point for this study. The VF/VT was defined as any episode of fatal ventricular tachyarrhythmia or any appropriate shock. In accordance with the presence or absence of VF/VT events within 5 years, all patients were divided into VF/VT group (n=6) and non-VF/VT group (n=20).Various clinical parameters were compared between the two groups. For analysis of autonomic nervous function, heart rate variability (HRV) and pupil function were evaluated.

Results

The mean age was 54±17 years old. There is no differences between the two groups in clinical parameters. In analysis of HRV, the high-frequency component (0.15–0.40 Hz; HF), low frequency component (0.04–0.15 Hz; LF) and the LF/HF ratio were analyzed over 24 h. LF/HF ratio was significantly lower over 24h in VF/VT groups in comparison with non-VF/VT groups [day-time; 1.8 (1.2–5.6) vs. 5.2 (3.4–8.8), p=0.048, night-time; 1.2 (1.1–1.3) vs. 3.9 (2.5–8.7), p=0.003]. Furthermore, in analysis of pupil function, right/left miosis ratio was higher in VT/VF groups in comparison with non-VT/VF groups [right pupil; 0.39 (0.37–0.59) vs. 0.34 (0.28–0.38), p=0.035, left pupil; 0.43 (0.36–0.50) vs. 0.33 (0.28–0.40), p=0.049]. In plasma total salusin-β levels, the VF/VT groups exhibited significantly lower than non-VF/VT groups (55.2±14.6 vs. 73.2±22.2, p=0.039, Figure).

Conclusions

Salusin-β was associated with the occurrence of VF/VT in Brugada syndrome. Salusin-β might be useful to identify high-risk patients for the occurrence of VT/VF events in Brugada syndrome.

Funding Acknowledgement

Type of funding source: None

Usefulness of peripheral-pressure-directed balloon pulmonary angioplasty for chronic thromboembolic pulmonary hypertension

Background

Balloon pulmonary angioplasty (BPA) in expert center may be considered in patients with chronic thromboembolic pulmonary hypertension (CTEPH) who are technically non-operable for pulmonary endarterectomy. BPA based on objective quantitative methods has not been established. The endpoint at BPA sessions has not been clarified yet.

Objectives

The purpose of this study was to investigate the usefulness of BPA according to peripheral pressure measured by pressure wire or catheter.

Methods

This study included consecutive 143 CTEPH who underwent cardiopulmonary exercise test with right heart catheterization after BPA. All patients were divided into 2 groups such as angio-guided (n=47) group or pressure-guidedgroup (n=96). In pressure-guided group, the pulmonary arterial pressure (PAP) proximal and distal to the target lesion and the ratio of the 2 pressures were measured by the pressure wire or catheter. the endpoint was determined to when the pressure ratio of distal to proximal pressures was &gt;0.7 to 0.8 finally. The dilation was stopped when the distal mean PAP after each dilation reached 35 mm Hg and when the baseline mean PAP was &gt;35 mm Hg. Changes of hemodynamic parameters such as PAP and pulmonary vascular resistance (PVR) from baseline, and mean PAP and PVR at peak oxygen consumption, and pulmonary arterial pressure – cardiac output (PA-CO) slope were compared between two groups. All data except changes of hemodynamics from baseline were expressed by median [25th percentile-75th percentile]. Changes of hemodynamics from baseline were expressed by average [95% confidence interval]

Results

The median age and male were 66 [56–72] years old and 35. There were no significant differences in number of sessions and dilated vessels between two groups (Angio-guided group vs. Pressure-guided group: 4 [3–6] vs. 4 [3–5], P&gt;0.05; 19 [12–22] vs. 17 [13–22], P&gt;0.05). Changes of PAP and PVR from baseline in pressure-guided group was significantly higher than in angio-guided groups (Angio-guided group vs. Pressure-guided group; ΔPAP: −19 [−20 to −17] vs. −20 [−21 to −20], P&gt;0.05; ΔPVR: −6.0 [−6.3 to −5.7] vs. −6.6 [−6.8 to −6.3], P&lt;0.01). Mean PAP and PVR at peak oxygen consumption (VO2) and PA-CO slope in pressure-guided group were significantly lower than in angio-guided group (Angio-guided group vs. Pressure-guided group; PAP at VO2: 43 [36–50] vs. 39 [34–43], P&lt;0.05; PVR at VO2: 2.7 [1.9–4.5] vs. 2.2 [1.6–2.9], P&lt;0.01; PA-CO slope: 3.8 [2.1–5.2] vs. 2.9 [1.9–4.0], P&lt;0.05).

Conclusions

Peripheral-pressure-directed BPA can improve hemodynamics at rest and exercise more effectively.

Funding Acknowledgement

Type of funding source: None

Activation of innate immunity by 14-3-3 ε, a new potential alarmin in osteoarthritis

OBJECTIVE

The innate immune system plays a central role in osteoarthritis (OA). We identified 14-3-3ε as a novel mediator that guides chondrocytes toward an inflammatory phenotype. 14-3-3ε shares common characteristics with alarmins. These endogenous molecules, released into extracellular media, are increasingly incriminated in sustaining OA inflammation. Alarmins bind mainly to toll-like receptor 2 (TLR2) and TLR4 receptors and polarize macrophages in the synovium. We investigated the effects of 14-3-3ε in joint cells and tissues and its interactions with TLRs to define it as a new alarmin involved in OA.

DESIGN

Chondrocyte, synoviocyte and macrophage cultures from murine or OA human samples were treated with 14-3-3ε. To inhibit TLR2/4 in chondrocytes, blocking antibodies were used. Moreover, chondrocytes and bone marrow macrophage (BMM) cultures from knockout (KO) TLRs mice were stimulated with 14-3-3ε. Gene expression and release of inflammatory mediators [interleukin 6 (IL-6), monocyte chemoattractant protein-1 (MCP-1), tumor necrosis factor alpha (TNFα)] were evaluated via reverse transcription quantitative polymerase chain reaction (RT-qPCR) and ELISA.

RESULTS

In vitro, 14-3-3ε induced gene expression and release of IL6 and MCP1 in the treated cells. The inflammatory effects of 14-3-3ε were significantly reduced following TLRs inhibition or in TLRs KO chondrocytes and BMM.

CONCLUSIONS

14-3-3ε is able to induce an inflammatory phenotype in synoviocytes, macrophages and chondrocytes in addition to polarizing macrophages. These effects seem to involve TLR2 or TLR4 to trigger innate immunity. Our results designate 14-3-3ε as a novel alarmin in OA and as a new target either for therapeutic and/or prognostic purposes.

55Identification of celastramycin as a novel therapeutic agent for pulmonary arterial hypertension - high-throughput screening of 5,562 compounds

Background

Pulmonary arterial hypertension (PAH) is characterized by enhanced proliferation of pulmonary artery smooth muscle cells (PASMCs) accompanying increased production of inflammatory factors and adaptation of mitochondrial metabolism to a hyperproliferative state. However, at present, since all the drugs in clinical use target pulmonary vascular dilatation, they may not be so effective for patients with advanced PAH.

Purposes

We aimed to discover a novel drug for PAH that inhibits PASMC proliferation.

Methods

In the first screening, we examined 5,562 compounds from our original library using high-throughput screening system to discover a compound that inhibits proliferation of PASMCs from PAH patients (PAH-PASMCs). In the second screening, we performed concentration-dependent assays and counter assays with PAH-PASMCs and PASMCs from healthy donors. We also performed apoptosis assays and mechanistic analysis for inflammation, reactive oxygen species (ROS), and mitochondrial function.

Results

We found that celastramycin, a benzoyl pyrrole-type compound originally found in a bacteria extract, inhibited the proliferation of PAH-PASMCs in a dose-dependent manner with minimal effects on PASMCs from healthy donors. Moreover, celastramycin inhibited proliferation with minimal increase in apoptosis and low rate of cell death. Then, we synthesized 25 analogues of celastramycin, and finally selected the lead compound that significantly inhibited proliferation of PAH-PASMCs and reduced cytosolic ROS levels. Mechanistic analysis demonstrated that celastramycin reduced the protein levels of hypoxia-inducible factor-1α, which was abnormally activated in PAH-PASMCs and impaired aerobic metabolism, and nuclear factor-κB, which induces pro-inflammatory signals, in PAH-PASMCs compared with vehicle controls, leading to reduced secretion of inflammatory cytokines. Importantly, celastramycin treatment reduced the ROS levels in PAH-PASMCs with increased protein levels of NF-E2-related factor 2 (Nrf2), a master regulator of cellular response against oxidative stress. Furthermore, celastramycin treatment improved mitochondrial energy metabolism with recovered mitochondrial network formation in PAH-PASMCs. We also discovered that celastramycin-mediated effects on these transcriptional modulators could be regulated by zinc finger C3H1 domain-containing protein, which is a binding partner of celastramycin. Finally, celastramycin treatment ameliorated pulmonary hypertension in three experimental animal models of PH in mice and rats, accompanied by reduced inflammatory changes in the lungs.

Conclusions

These results indicate that celastramycin ameliorates pulmonary hypertension through inhibition of excessive proliferation of PAH-PASMCs, for which its anti-inflammatory and beneficial effects on mitochondrial energy metabolism may be involved. Thus, celastramycin could be a novel drug for PAH as it exerts anti-proliferative effects on PAH-PASMCs.

P6009Poor outcomes in pulmonary arterial hypertension as a member of RNF213-associated vascular diseases

Background

A variant of c.14429G>A (p.Arg4810Lys, rs112735431) in the ring finger protein 213 gene (RNF213; NM_001256071.2) has been recently identified as a risk allele for pulmonary arterial hypertension (PAH), suggesting that PAH can be added as a new member of RNF213-associated vascular diseases including Moyamoya disease and peripheral pulmonary stenosis.

Purpose

Our aim was to identify the clinical features and outcomes of PAH patients with RNF213 p.Arg4810Lys variant.

Methods

Whole-exome sequencing was performed in 139 idiopathic (or possibly heritable) PAH patients. Hemodynamics and prognosis were evaluated in the patients with RNF213 p.Arg4810Lys variant and the patients with bone morphogenic protein receptor type 2 (BMPR2) mutations.

Results

The RNF213 p.Arg4810Lys variant was identified in a heterozygous state in 11 patients (7.9%). Time-course changes in hemodynamics after combination therapy in the patients with the RNF213 p.Arg4810Lys variant were significantly poorer compared with those in BMPR2 mutation carriers (n=36) (comparison of changes in mean pulmonary arterial pressure, P=0.007). The event-free rate of death or lung transplantation was significantly poorer in RNF213 p.Arg4810Lys variant carriers than in BMPR2 mutation carriers (5-year event-free rate since the introduction of prostaglandin I2 infusion, 0% vs. 93%, P<0.001) (Figure).

Time to death or lung transplantation

Conclusions

PAH patients with the RNF213 p.Arg4810Lys variant were associated with a poor reactivity to vasodilator drugs and poor clinical outcomes even in the recent era. Earlier consideration of lung transplantation might be required for RNF213 p.Arg4810Lys variant carriers developing PAH. Documentation of the RNF213 p.Arg4810Lys variant, as well as already known pathogenic genes, can provide clinically relevant information for therapeutic strategies, leading to a personalized approach for the treatment of PAH.

P6479Diagnostic and prognostic significance of serum levels of selenoprotein P in patients with pulmonary arterial hypertension

Background

Despite the recent progress in upfront combination therapy for pulmonary arterial hypertension (PAH), a useful biomarker for the disorder still remains to be developed. Selenoprotein P (SeP) is a glycoprotein secreted mainly from hepatocytes but also from other various kinds of cells, including pulmonary artery smooth muscle cells (PASMCs), to maintain selenium homeostasis and cellular energy metabolism. We have recently demonstrated that SeP expression in PASMCs is markedly up-regulated in PAH patients and plays crucial roles in the pathogenesis of the disorder. In this study, we thus examined whether serum levels of SeP could be a useful biomarker for the disorder.

Methods

In the experimental study, we performed gene expression microarray and in silico analyses to identify a novel therapeutic target for PAH. We also used the lung, serum, and cultured PAMSCs derived from patients with PAH for mechanistic experiments. In the clinical study, we enrolled a total of 65 consecutive patients with PAH who underwent right heart catheterization for hemodynamic assessment. We measured serum SeP levels and evaluated their prognostic impacts during follow-up (mean 1,520 days, IQR: 1,393–1,804 days). Serum SeP level was measured using a newly developed sol particle homogeneous immunoassay. As controls, we collected serum samples from 20 controls without any known cardiac disorders evaluated by hematological examination, echocardiography, and coronary angiography. In PAH patients, we examined the relationship between baseline SeP levels and composite endpoint of all-cause death and lung transplantation. The correlation between the absolute changes in SeP and those in hemodynamic parameters during follow-up were also examined.

Results

In the experimental study, SeP promoted PASMC proliferation through increased oxidative stress and mitochondrial metabolic dysfunction, which were associated with activated HIF-1α and dysregulated glutathione metabolism. In the clinical study, PAH patients showed significantly higher levels of serum SeP compared with controls (3.07±0.57 vs. 2.43±0.25 mg/L, P<0.0001). Higher SeP levels (cut-off point, 3.47 mg/L) were significantly associated with the composite endpoint of all-cause death and lung transplantation in PAH patients [HR: 4.85 (1.42 to 16.6), P<0.01]. Importantly, we found that absolute changes in SeP levels in PAH patients significantly correlated with those in mean pulmonary artery pressure, pulmonary vascular resistance, and cardiac index in response to PAH-specific therapy (R=0.78, 0.76, and −0.71, respectively, all P<0.0001). Furthermore, the increases in SeP levels during follow-up predicted the poor outcome in PAH patients [Figure, HR: 4.29 (1.27 to 14.4), P<0.05].

Figure 1

Conclusions

These results indicate that SeP is a novel therapeutic target of PAH and that serum SeP levels are a novel biomarker for diagnosis and assessment of treatment efficacy and long-term prognosis in PAH patients.

Acknowledgement/Funding

Grants-in-aid for Scientific Research from the Japan Agency for Medical Research and Development, Tokyo, Japan (16ek0109176h0001, 17ek0109227h0001).

Neonatal oral fluid as a transmission route for bifidobacteria to the infant gut immediately after birth

Bifidobacteria are one of the most abundant bacterial groups in the infant gut microbiota and are closely associated with infant health and can potentially affect health in later life. However, the details regarding the source of bifidobacteria have yet to be completely elucidated. This study aimed to assess neonatal oral fluid (OF) as a transmission route for bifidobacteria to the infant gut during delivery. Neonatal OF and infant feces (IF) were collected immediately and one month after birth from 15 healthy vaginally delivered newborns. Bifidobacterium strains were isolated from OF and IF samples, and the similarity of strains between the OF-IF pairs was evaluated based on the average nucleotide identity (ANI) value. The 16S rRNA gene sequencing results revealed the presence of Bifidobacteriaceae at >1% relative abundance in all OF samples. Bifidobacterium strains were isolated from OF (9/15) and IF (11/15) samples, and those sharing high genomic homology (ANI values >99.5%) between the neonatal OF and IF samples were present in one-third of the OF-IF pairs. The results of this study indicate that viable bifidobacteria are present in neonatal OF and that OF at birth is a possible transmission route of bifidobacteria to the infant gut.

Visualization of Aneurysmal Neck and Dome after Coiling with 3D Multifusion Imaging of Silent MRA and FSE-MR Cisternography

BACKGROUND AND PURPOSE

Our aim was to visualize the precise configuration of the aneurysmal neck and dome with/without remnants combined with a coiled dome after coiling treatment for cerebral aneurysms. We developed 3D multifusion imaging of silent MRA and FSE-MR cisternography.

MATERIALS AND METHODS

We examined 12 patients with 3D multifusion imaging by composing 3D images reconstructed from TOF-MRA, silent MRA, and FSE-MR cisternography. The influence of magnetic susceptibility artifacts caused by metal materials affecting the configuration of the aneurysmal complex with coiling was assessed in a single 3D image.

RESULTS

In all cases, TOF-MRA failed to depict the aneurysmal neck complex precisely due to metal artifacts, whereas silent MRA delineated the neck and parent arteries at the coiled regions without serious metal artifacts. FSE-MR cisternography depicted the shape of the coiled aneurysmal dome and parent artery complex together with the brain parenchyma. With the 3D multifusion images of silent MRA and FSE-MR cisternography, the morphologic status of the coiled neck and parent arteries was clearly visualized with the shape of the dome in a single 3D image.

CONCLUSIONS

Silent MRA is a non-contrast-enhanced form of MRA. It depicts the coiled neck complex without serious metal artifacts. FSE-MR cisternography can delineate the shape of the coiled dome. In this small feasibility study, 3D multifusion imaging of silent MRA and FSE-MR cisternography allowed good visualization of key features of coiled aneurysms. This technique may be useful in the follow-up of coiled aneurysms.

Purified thioredoxin reductase from O2-sensitive Bifidobacterium bifidum degrades H2O2 by interacting with alkyl hydroperoxide reductase

Bifidobacterium is beneficial for host health and exhibits different O₂ sensitivity levels among species or strains via unknown mechanisms. Bifidobacterium bifidum JCM1255^T, a type species of Bifidobacterium, is an O₂-sensitive bacterium that can grow under low-O₂ (5%) conditions, and the growth of this species is inhibited under high-O₂ conditions (10% ∼) with accumulation of H₂O₂. We previously reported that NADH or NAD(P)H oxidase-active fractions were detected during purification using microaerobically grown B. bifidum cells, and the active enzyme was purified from the NADH oxidase-active fraction. The purified enzyme was identified as b-type dihydroorotate dehydrogenase (DHODb) and characterized as a dominant H₂O₂ producer in B. bifidum. In this study, we performed further purification of the enzyme from the NAD(P)H oxidase-active fraction and characterized the purified enzyme as a part of the H₂O₂ degradation system in B. bifidum. This purified enzyme was identified as thioredoxin reductase (TrxR); the NAD(P)H oxidase activity of this enzyme was not expressed in anaerobically grown B. bifidum, and mRNA expression was induced by O₂ exposure. Furthermore, the purified B. bifidum TrxR interacted with recombinant alkyl hydroperoxide reductase (rAhpC) and exhibited NAD(P)H peroxidase activity. These results suggest that TrxR responds to O₂ and protects B. bifidum from oxidative stress by degrading H₂O₂ via the TrxR-AhpC system.