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The gut microbiome plays an important role in the immune system and has attracted attention as a biomarker of several diseases, including cancer. In this study, we examined the relationship between the gut microbiome and lung cancer progression.Female never-smokers diagnosed with lung adenocarcinoma were consecutively enrolled between May 2018 and August 2019, and fecal samples were collected. Principal coordinate analyses were performed using Bray-Curtis distance matrices to investigate the effects of clinical variables (age, body mass index, Tumor-Node-Metastasis stage, T category, N category, M category, primary tumor size, performance status, and EGFR mutation status) on the gut microbial community.A total of 37 patients were enrolled. T category and primary tumor size were significantly correlated with the gut microbial community (p=0.018 and 0.041, respectively).This study identified the gut microbiome as a promising biomarker of lung cancer progression.

Laparoscopic sleeve gastrectomy (LSG) is an important therapeutic option for morbidly obese patients. Although LSG promotes sufficient weight loss, how LSG changes plasma metabolites remains unclear. We assessed changes in plasma metabolite levels after LSG. We collected plasma samples from 15 morbidly obese Japanese patients before and 3 months after LSG. A total of 48 metabolites were quantified using capillary electrophoresis time‐of‐flight mass spectrometry‐based metabolomic profiling. Branched chain amino acids, several essential amino acids, choline, 2‐hydroxybutyric acid, 2‐oxoisovaleric acid and hypoxanthine were significantly decreased after LSG. Tricarboxylic acid cycle metabolites, including citric acid, succinic acid and malic acid, were significantly elevated after LSG. This is the first report to show dynamic alterations in plasma metabolite concentrations, as assessed using capillary electrophoresis time‐of‐flight mass spectrometry, in morbidly obese patients after LSG. Our results might show how LSG helps improve obesity, in part through metabolic status changes, and propose novel therapeutic targets to ameliorate obesity., Dynamic alterations in plasma metabolite concentrations in morbidly obese patients after laparoscopic sleeve gastrectomy.

Inflammation has been suggested to play a key role in the pathogenesis of atrial fibrillation (AF). Our hypothesis was that this inflammation, mediated by intermediate monocytes and toll-like receptor 4 (TLR4), causes the formation and expansion of low-voltage zones (LVZs). Prior to ablation, the monocyte subsets of 78 AF patients and TLR4 expression of 66 AF patients were analyzed via a flow cytometric analysis. Based on the CD14/CD16 expression, the monocytes were divided into three subsets: classical, intermediate, and non-classical. At the beginning of the ablation session, voltage mapping was performed. LVZs were defined as all bipolar electrogram amplitudes of

Background: The gut microbiome plays an important role in the immune system and has attracted attention as a biomarker of various diseases, including cancer. As such, we examined the relationship between the gut microbiome and lung cancer progression. In addition, we assessed the correlation between the gut microbiome and epidermal growth factor receptor (EGFR) mutation status.Methods: Female never-smokers diagnosed with lung adenocarcinoma were consecutively and prospectively enrolled between May 2018 and August 2019. Fecal samples were collected within 1 month before or after diagnosis and before administration of any lung cancer treatment. Principal coordinate analyses were retrospectively performed using Bray-Curtis distance matrices to investigate the effects of clinical variables (age, body mass index, Tumor-Node-Metastasis stage, T category, N category, M category, primary tumor size, performance status, and EGFR mutation status) on the gut microbial community. A correlation analysis was also performed to determine the strength of association between the dominant taxonomy (comprising ≥1% of the relative abundance of bacterial DNA sequences) and clinical variables.Results: A total of 37 patients were enrolled. T category and primary tumor size were significantly correlated with the gut microbial community (p=0.018 and 0.041, respectively). At the genus level, a significant positive correlation was observed between the relative abundance of Faecalibacterium and both T category (correlation coefficient, R=0.51, p=0.0013) and primary tumor size (R=0.37, p=0.024), whereas a significant negative correlation was observed between the relative abundances of Fusicatenibacter and Bacteroides and T category (R=−0.35, p=0.034 and R=−0.32, p=0.05, respectively) and primary tumor size (R=−0.36, p=0.029 and R=−0.41, p=0.012, respectively). EGFR mutation status had no statistically significant effect on the gut microbial community (p=0.11). However, the relative abundances of Bifidobacterium and Faecalibacterium were significantly higher in EGFR mutation–negative patients than EGFR mutation–positive patients (p=0.012 and 0.041), whereas the relative abundance of Blautia was significantly lower in EGFR mutation–negative patients (p=0.036).Conclusions: This is the first study identifying the gut microbiome as a promising biomarker of lung cancer progression. Further elucidation of the role of the gut microbiome in lung cancer progression could facilitate development of new treatments for lung cancer.

Faecal lipopolysaccharides (LPS) have attracted attention as potent elements to explain a correlation between the gut microbiota and cardiovascular disease (CVD) progression. However, the underlying mechanism of how specific gut bacteria contribute to faecal LPS levels remains unclear. We retrospectively analysed the data of 92 patients and found that the abundance of the genus Bacteroides was significantly and negatively correlated with faecal LPS levels. The controls showed a higher abundance of Bacteroides than that in the patients with CVD. The endotoxin units of the Bacteroides LPS, as determined by the limulus amoebocyte lysate (LAL) tests, were drastically lower than those of the Escherichia coli LPS; similarly, the Bacteroides LPS induced relatively low levels of pro-inflammatory cytokine production and did not induce sepsis in mice. Fermenting patient faecal samples in a single-batch fermentation system with Bacteroides probiotics led to a significant increase in the Bacteroides abundance, suggesting that the human gut microbiota could be manipulated toward decreasing the faecal LPS levels. In the clinical perspective, Bacteroides decrease faecal LPS levels because of their reduced LAL activity; therefore, increasing Bacteroides abundance might serve as a novel therapeutic approach to prevent CVD via reducing faecal LPS levels and suppressing immune responses.

Background Gut microbiome composition or circulating microbiome-related metabolites in patients with heart failure (HF) have not been investigated at different time points (i.e., in the decompensated (Decomp) and compensated (Comp) phases). Methods and Results: We prospectively enrolled 22 patients admitted for HF and 11 age-, sex-, and comorbidity-matched hospitalized control subjects without a history of HF. Gut flora and plasma microbiome-related metabolites were evaluated by amplicon sequencing of the bacterial 16S ribosomal RNA gene and capillary electrophoresis time-of-flight mass spectrometry, respectively. HF patients were evaluated in both the Decomp and Comp phases during hospitalization. The phylum Actinobacteria was enriched in HF patients compared with control subjects. At the genus level, Bifiodobacterium was abundant while Megamonas was depleted in HF patients. Meanwhile, plasma concentration of trimethylamine N-oxide (TMAO), a gut microbiome-derived metabolite, was increased in HF patients (Decomp HF vs. control, P=0.003; Comp HF vs. control, P=0.004). A correlation analysis revealed positive correlations between the abundance of the genus Escherichia/Shigella and levels of TMAO and indoxyl sulfate (IS, a microbe-dependent uremic toxin) in Comp HF (TMAO: r=0.62, P=0.002; IS: r=0.63, P=0.002). Escherichia/Shigella was more abundant in Decomp than in Comp HF (P=0.030). Conclusions Our results suggest that gut microbiome composition and microbiome-related metabolites are altered in HF patients.

Background: It is increasingly recognized that gut microbiota play a pivotal role in the development of atherosclerotic cardiovascular disease. Previously, we have reported that the abundance of genus Bacteroides is lower in patients with coronary artery disease (CAD) than in patients without CAD with coronary risk factors or in healthy volunteers. However, it remains unclear which and how specific gut bacteria contribute to the progression of atherosclerosis. Methods: We recruited patients with CAD patients and controls without CAD with coronary risk factors. We then compared gut microbial composition using 16S ribosomal RNA gene sequencing in fecal samples to detect species with differential abundance between 2 groups. Subsequently, we used atherosclerosis-prone mice to study the mechanisms underlying the relationship between such species and atherosclerosis. Results: Human fecal 16S ribosomal RNA gene sequencing revealed a significantly lower abundance of Bacteroides vulgatus and Bacteroides dorei in patients with CAD. This significant differential abundance was confirmed by quantitative polymerase chain reaction. Gavage with live B. vulgatus and B. dorei attenuated atherosclerotic lesion formation in atherosclerosis-prone mice, markedly ameliorating endotoxemia followed by decreasing gut microbial lipopolysaccharide production, effectively suppressing proinflammatory immune responses. Furthermore, fecal lipopolysaccharide levels in patients with CAD were significantly higher and negatively correlated with the abundance of B. vulgatus and B. dorei . Conclusions: Our translational research findings identify a previously unknown link between specific gut bacteria and atherosclerosis. Treatment with live B. vulgatus and B. dorei may help prevent CAD. Clinical Trial Registration: URL: https://upload.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000018051 . Unique identifier: UMIN000015703.

Aims Vascular inflammation via T-cell-mediated immune responses has been shown to be critically involved in the pathogenesis of abdominal aortic aneurysm (AAA). T-cell coinhibitory molecule cytotoxic T-lymphocyte–associated antigen-4 (CTLA-4) is known to act as a potent negative regulator of immune responses. However, the role of this molecule in the development of AAA remains completely unknown. In the present study, we determined the effects of CTLA-4 overexpression on experimental AAA. Methods and results We continuously infused 12-week-old CTLA-4 transgenic (CTLA-4-Tg)/apolipoprotein E–deficient (Apoe−/−) mice (n=35) or control Apoe−/− mice (n=40) fed a high-cholesterol diet with angiotensin II by implanting osmotic mini-pumps and evaluated the development of AAA. Ninety percent of angiotensin II-infused mice developed AAA, with 50% mortality because of aneurysm rupture. Overexpression of CTLA-4 significantly reduced the incidence (66%), mortality (26%), and diameter (18%) of AAA (incidence: P=0.0104; mortality: P=0.031; diameter: P=0.011). These protective effects were associated with a decreased number of effector CD4+ T cells and the downregulated expression of costimulatory molecules CD80 and CD86, ligands for CTLA-4, on CD11c+ dendritic cells in lymphoid tissues. In addition, by performing in situ zymography of the abdominal aortic aneurysm lesions, we observed a trend toward a decrease in MMP activity in the aneurysmal lesion following overexpression of CTLA-4. Finally, CTLA-4-Tg/Apoe−/− mice had reduced macrophage and CD4+ T cell accumulation and MMP activity in the aneurysmal lesion, leading to attenuated aortic inflammation, preserved vessel integrity, and decreased susceptibility to AAA and aortic rupture. Conclusion Our findings suggest that CTLA-4 protects against AAA by suppressing immunoinflammatory responses and could be an attractive therapeutic target for AAA.