Toll-Like Receptor 7-Expressed Macrophages Are Involved in the Pathogenesis of Esophageal Achalasia and Esophagogastric Junction Outflow Obstruction.

INTRODUCTION: Esophageal achalasia is a typical esophageal motility disorder (EMD). Although viral infections have been hypothesized to play a role in the pathogenesis of esophageal achalasia, its etiology remains unclear. This study used esophageal muscle layer specimens collected during per-oral endoscopic myotomy (POEM) procedures to investigate the association between esophageal achalasia and esophagogastric junction outflow obstruction (EGJOO) and pattern recognition receptors. METHODS: Patients with esophageal achalasia and EGJOO who underwent POEM were allocated to the EMD group. Biopsies of the inner circular muscle were conducted during the POEM procedure. The control group comprised individuals diagnosed with esophageal squamous cell carcinoma who underwent surgical resection. Expression of pattern recognition receptors, including Toll-like receptor (TLR) 7, was examined by polymerase chain reaction. Immunohistochemical staining was performed to determine TLR7 expression sites in the esophageal muscle layer, and the relationship between TLR7 mRNA expression and clinical score was investigated. RESULTS: Our analysis revealed a notable upregulation of TLR7 mRNA levels within the muscle layer of esophageal achalasia and EGJOO, in contrast to those of control specimens. In contrast, the correlation between TLR7 and clinical score was not significant. Immunohistochemical staining revealed increased numbers of TLR7-expressing macrophages between the muscle layers. CONCLUSIONS: TLR7-expressing macrophages are involved in the innate immune response underlying esophageal achalasia and EGJOO. This result will lead to the elucidation of new pathogenetic mechanisms and the development of novel therapeutic targets.

Effect of Liver Fibrosis on Oral and Gut Microbiota in the Japanese General Population Determined by Evaluating the FibroScan-Aspartate Aminotransferase Score.

The association between liver fibrosis and oral or gut microbiota has been studied before. However, epidemiological studies in the general population are limited owing to the difficulty of noninvasive liver-fibrosis assessment. FibroScan-asparate aminotransferase (FAST) scores can be used to accurately and non-invasively evaluate liver fibrosis. This study aimed to determine the association between liver fibrosis and oral or gut microbiota using the FAST score in the general population. After propensity score matching of 1059 participants based on sex, age, body mass index, homeostasis model assessment of insulin resistance, and triglyceride levels, 125 (non-liver-fibrosis group, 100; liver fibrosis group, 25) were included. The diversity of gut microbiota differed significantly between the two groups; however, no significant differences were noted in their oral microbiota. The liver fibrosis group showed an increase in the relative abundance of Fusobacteria strains and a decrease in the relative abundance of Faecalibacterium, with the presence of Fusicatenibacter in the gut microbiota. Feacalibacterium was not identified as an independent factor of liver fibrosis in adjusting the fatty liver index. In the general population, gut microbiota may be more involved in liver fibrosis than oral microbiota.

Association between reactive oxygen species production in neutrophils and liver fibrosis in the general population.

Fibrosis, induced by reactive oxygen species (ROS) production in neutrophils, has harmful effects on the liver and various other organs. However, little is known about the association between liver fibrosis and ROS levels in neutrophils in the general population. This large-scale epidemiological study aimed to determine the association between liver fibrosis and neutrophil-generated ROS levels according to age and sex in the general population. This cross-sectional study included 1,000 participants from a district health promotion project. Participants were grouped based on sex (male; female) and age (young, <65 years; old, ≥65 years). The four groups were as follows: male, young (n = 289); male, old (n = 100); female, young (n = 425); and female, old (n = 186). Liver fibrosis was assessed using the fibrosis 4 (FIB-4) index, aspartate aminotransferase-to-platelet ratio index (APRI), and non-alcoholic fatty liver disease (NAFLD) fibrosis score (NFS). Basal and stimulated ROS were considered in the analysis. Multiple linear analyses showed (1) significant positive correlations between all liver fibrosis scores and basal ROS in the young groups, and (2) significant negative correlations between NFS and stimulated ROS in females. Preventing liver fibrosis through neutrophil-related immune system enhancement may avert the development of lifestyle-related diseases and infections.

The Impact of Japanese Dietary Patterns on Metabolic Dysfunction-Associated Steatotic Liver Disease and Liver Fibrosis.

This study aimed to investigate the effect of Japanese dietary patterns on metabolic dysfunction-associated steatotic liver disease (MASLD) and liver fibrosis. After excluding factors affecting the diagnosis of hepatic steatosis, 727 adults were analyzed as part of the Health Promotion Project. The dietary patterns of the participants were classified into rice, vegetable, seafood, and sweet based on their daily food intake. Liver stiffness measurements and controlled attenuation parameters were performed using FibroScan. Energy and nutrient intake were calculated using the Brief-type Self-administered Diet History Questionnaire. Univariate and multivariate analyses were used to identify the risk factors for liver fibrosis within the MASLD population. The vegetable group had significantly lower liver fibrosis indicators in the MASLD population than the rice group. The multivariate analysis identified a body mass index ≥ 25 kg/m2 (odds ratio [OR], 1.83; 95% confidence interval [CI], 1.01-1.83; p = 0.047) and HOMA-IR ≥ 1.6 (OR, 3.18; 95% CI, 1.74-5.78; p < 0.001) as risk factors for liver fibrosis, and vegetable group membership was a significant low-risk factor (OR, 0.38; 95% CI, 0.16-0.88; p = 0.023). The multivariate analysis of nutrients in low-risk foods revealed high intake of α-tocopherol (OR, 0.74; 95% CI, 0.56-0.99; p = 0.039) as a significant low-risk factor for liver fibrosis. This study suggests that a vegetable-based Japanese dietary pattern, through the antioxidant effects of α-tocopherol, may help prevent liver fibrosis in MASLD and the development of MASLD.

Reduced Equol Production and Gut Microbiota Features in Men With Lean Nonalcoholic Fatty Liver Disease.

Patients with lean nonalcoholic fatty liver disease (NAFLD) may have different metabolic profiles than those with NAFLD. Estrogenic activity is associated with NAFLD pathogenesis. We evaluated the production ability of equol, which has estrogenic activity, in lean NAFLD and assessed their gut microbiota in relation to their equol-producing ability. Among 684 adult participants, 276 (40%) had NAFLD and 293 (43%) were equol producers. The rates of equol producers in the normal and NAFLD groups were 43% and 42%, respectively. Among the patients with NAFLD, 55 (20%) had lean NAFLD of which 18 (33%) were equol producers. The rate of equol production in men with lean NAFLD was 8%, which was the lowest, while the corresponding rate in the other participants was approximately 40%. The gut microbiota composition of equol producers and nonproducers showed many significant differences. The gut microbiota of men with lean NAFLD showed increased abundance of Caulobacter and decreased abundances of Slackia and Terrisporobacter. Thus, almost all men with lean NAFLD lacked equol-producing ability, and their gut microbiota showed a reduced abundance of Slackia, which is related to equol production. The pathology of lean NAFLD in men may be strongly associated with equol-producing ability and gut microbiota.

Evaluation of metabolic dysfunction-associated fatty liver disease using FibroScan, diet, and microbiota: A large cross-sectional study.

OBJECTIVE: We evaluated the clinical characteristics of metabolic dysfunction-associated fatty liver disease (MAFLD) to evaluate the usefulness of the MAFLD diagnostic criteria in a resident health survey. METHODS: In 1056 participants of a health survey, we compared obesity, diabetes, metabolic dysregulation, FibroScan-aspartate aminotransferase (FAST) score, dietary habits, and gut microbiota between healthy individuals and participants with MAFLD and Nonalcoholic fatty liver disease (NAFLD). RESULTS: The proportion of participants with MAFLD in the fatty liver was higher than that with NAFLD (88.1% vs. 75.5%, respectively). Of 36 participants with a FAST score > 0.35, 29 (80.6%) participants had MAFLD and 23 (63.9%) participants had NAFLD. Of 29 patients with liver fibrosis, 26 (89.7%) participants had obesity and metabolic dysregulation. In the evaluation of diet, the total energy, protein, dietary fiber, and salt intake were significantly higher in participants with MAFLD than those in participants without fatty liver. In the microbiota analysis, the results of the linear discriminant analysis effect size analysis revealed nine bacterial genera that were significantly different in participants with MAFLD in comparison with participants without fatty liver. Of these genera, the relative abundance of Blautia was especially low in participants with MAFLD. CONCLUSION: In a resident health survey, participants with MAFLD had a higher proportion of fatty liver than those with NAFLD. MAFLD criteria could help in improved screening of participants with liver fibrosis. Therefore, the MAFLD criteria could be a useful diagnostic tool for aggressively identifying participants with a high risk of fatty liver. Additionally, Blautia might be involved in the development of MAFLD.