Clostridium butyricum alleviates intestinal low-grade inflammation in TNBS-induced irritable bowel syndrome in mice by regulating functional status of lamina propria dendritic cells.

BACKGROUND: Irritable bowel syndrome (IBS) is one of the most common functional gas-troenterological diseases characterized by abnormal visceral sensitivity and low-grade inflammation. The role of Clostridium butyricum (C. butyricum) in reducing intestinal low-grade inflammation via immune pathways has been well defined. However, the detailed mechanisms of the effects of C. butyricum on intestinal mucosal immunity, especially on immune cells of the lamina propria, remain unclear. Dendritic cells (DCs), which are important immune cells, secrete proinflammatory cytokines (IL-1ß, IL-6, and others) and express T cell immuno-globulin and mucin domain-3 (TIM3), promoting proliferation and activation of DCs, and mediating Th1 and Th17 inflammatory responses. AIM: To investigate the role of DCs in the development of IBS in a rat model and to understand the regulation of DCs after C. butyricum intervention. METHODS: An IBS animal model was established using C57BL/6 mice, and C. butyricum was continuously administered via the intragastric route to simulate different intestinal immune states. Intestinal visceral hypersensitivity and histopathology were assessed using the abdominal withdrawal reflex (AWR) test and hematoxylin & eosin (H&E) staining, respectively. The expression of proinflammatory cytokines (IL-1ß and IL-6) and TIM3 was analyzed by Western blot analysis and real-time PCR. Flow cytometry was applied to analyze the quantity, function, and membrane molecule TIM3 of the lamina propria dendritic cells (LPDCs). The regulatory effect of C. butyricum was verified in bone marrow-derived dendritic cells by in vitro experiments. RESULTS: The secretion of proinflammatory cytokines (IL-1ß and IL-6) in mice with IBS was significantly increased compared with that of the control group, which suggested that the intestinal mucosa in mice with IBS was in a low-grade inflammatory state. The expression of CD11C+CD80+ and CD11c+TIM3+ in intestinal LPDCs in mice with IBS increased significantly. Meanwhile, the cytokines (IL-1ß and IL-6) were significantly reduced after the intervention with probiotic C. butyricum. The amount and function of LPDCs and the TIM3 on the surface of the LPDCs were decreased with the alleviation of the intestinal inflammatory response. CONCLUSION: The results suggest that C. butyricum regulates the amount and functional status of LPDCs in the intestinal mucosa of mice with IBS, and therefore modulates the local immune response in the intestine.

Hepatic venous pressure gradient is a useful predictor in guiding treatment on prevention of variceal rebleeding in cirrhosis.

BACKGROUND: The best therapy to prevent esophageal variceal (EV) rebleeding in cirrhotic patients who are non-responsive to pharmacological therapy have not been determined. AIMS: To evaluate efficacy of a strategy to assign different treatments according to hepatic vein pressure gradient (HVPG) values to prevent EV rebleeding in non-responders. METHODS: This study is a non-randomized controlled prospective study. 109 cirrhotic patients with EV bleeding who were non-responders based on two HVPG measurements were enrolled and divided two groups: 55 patients (EVL+ß-blocker group) were treated with endoscopic variceal ligation (EVL) and nonselective ß-blocker; 54 patients (HVPG-guided group) were treated with EVL and nonselective ß-blocker if HVPG ≤ 16 mmHg (low-HVPG), with percutaneous transhepatic variceal embolization (PTVE) if HVPG > 16 mmHg and ≤ 20 mmHg (medium-HVPG), or with transjugular intrahepatic portosystemic shunt (TIPS) if HVPG > 20 mmHg (high-HVPG). Patients were followed up for rebleeding and mortality. RESULTS: The mean follow-up period was 17.0 months; rebleeding was higher in the EVL+ß-blocker group than HVPG-guided group (25.5%, 9.3%, P = 0.026); 3-year probability of rebleeding in the EVL+Beta-blocker group increased with elevated levels of HVPG (12.5% vs 46.4% vs 64.9%, χ(2) = 11.551, P = 0.003), and 3-year probability of survival was no difference (96.6% vs 85.7% vs 90.9%, χ(2) = 2.638, P = 0.267). Rebleeding rate in PTVE group (7.7%) was lower than that in EVL+ß-blockergroup with medium-HVPG (35.7%), but there was no difference. Rebleeding rate in TIPS group (7.7%) was lower than that in EVL+ß-blockergroup with high-HVPG (45.5%), but there was no difference. CONCLUSIONS: HVPG measurement was useful for making decisions to select EVL and Beta-blocker, PTVE or TIPS in secondary prophylaxis. HVPG-guided treatment is feasible and effective in preventing esophageal varices rebleeding.

Fas -670A/G (rs1800682) polymorphism and digestive cancer risk in Asians: a meta-analysis.

OBJECTIVES: Tumorigenesis is a multistep process that begins with the abrogation of normal controls of apoptosis and cell proliferation, and the Fas receptor-ligand system is a key regulator of apoptosis. The Fas -670 A/G single-nucleotide polymorphism (SNP) has been demonstrated to affect the expression of the Fas gene by altering the transcriptional activity in this gene's promoter. However, the association between the Fas -670 A/G polymorphism and digestive cancer risk is still controversial and ambiguous in the Asian population, so we conducted a meta-analysis to confirm and clarify the association between the Fas -670 A/G polymorphism and digestive cancer. MATERIALS AND METHODS: A search of PubMed, China National Knowledge Infrastructure (CNKI), and WanFang databases was conducted and encompassed all available articles that had been published up to July 20, 2013. Overall, 15 case-control studies containing 3692 cases and 4895 controls were retrieved based on search criteria for digestive cancer susceptibility related to -670A/G SNP. Odds ratios (ORs) and 95% confidence intervals (CIs) were used to assess the strength of this association. RESULTS: In the overall analysis, the country type and source of control subgroups, no association between the Fas -670 A/G polymorphism and digestive cancer risk was found. However, in the digestive cancer-type subgroups, a significant protective effect was detected between Fas -670 A/G polymorphism and hepatocellular carcinoma in Asians (AG vs. GG: OR=0.89, 95% CI=0.80-0.99; AA+AG vs. GG: OR=0.93, 95% CI=0.87-1.00). CONCLUSIONS: Our investigations demonstrated that the Fas -670 A/G polymorphism might decrease the hepatocellular carcinoma risk in Asian populations. Further studies based on larger sample sizes, other ethnicities, and gene-environment interactions should be conducted to further understand the role of Fas -670 A/G polymorphism in digestive cancer risk.