Molecular regulation mechanism of intestinal stem cells in mucosal injury and repair in ulcerative colitis

Ulcerative colitis(UC)is a chronic nonspecific inflammatory disease with complex causes.The main pathological changes were intestinal mucosal injury.Leucinerich repeat-containing G protein coupled receptor 5(LGR5)-labeled small intestine stem cells(ISCs)were located at the bottom of the small intestine recess and inlaid among Paneth cells.LGR5+small ISCs are active proliferative adult stem cells,and their self-renewal,proliferation and differentiation disorders are closely related to the occurrence of intestinal inflammatory diseases.The Notch signaling pathway and Wnt/β-catenin signaling pathway are important regulators of LGR5-positive ISCs and together maintain the function of LGR5-positive ISCs.More importantly,the surviving stem cells after intestinal mucosal injury accelerate division,restore the number of stem cells,multiply and differentiate into mature intestinal epithelial cells,and repair the damaged intestinal mucosa.Therefore,in-depth study of multiple pathways and transplantation of LGR5-positive ISCs may become a new target for the treatment of UC.

腺垂体功能减退症误诊为胃肠炎1例

背景腺垂体功能减退临床表现不典型,复杂多样,易造成误诊.病例简介患者,男,72岁,因“间断腹泻10年余”入院,既往诊断为胃肠炎,口服“氟哌酸、思密达”等疗效欠佳,住院期间出现反应迟钝、嗜睡、对答不切题等精神症状,查甲状腺激素水平、性激素水平、皮质醇水平均明显降低,脑垂体MR显示空泡蝶鞍、垂体受压,诊断为腺垂体功能减退,给予激素治疗后患者神志恢复正常,腹泻消失.结论腺垂体功能减退临床表现不典型,复杂多样,易出现漏诊及误诊,若诊治不及时可出现垂体危象,危及生命.在临床中腺垂体功能减退症并不少见,对于皮肤干燥苍白、弹性差或浮肿、贫血、纳差、便秘、毛发脱落、畏冷、表情淡漠、音调低沉、反应迟钝、虚弱无力、食欲减退、恶心、呕吐、体重减轻、心率缓慢、心音低钝、血压下降、低血糖等表现的患者要考虑是否存在腺垂体功能减退症.

Fecal microbiota transplantation in the metabolic diseases:Current status and perspectives

With the development of microbiology and metabolomics,the relationship between the intestinal microbiome and intestinal diseases has been revealed.Fecal microbiota transplantation(FMT),as a new treatment method,can affect the course of many chronic diseases such as metabolic syndrome,malignant tumor,autoimmune disease and nervous system disease.Although the mechanism of action of FMT is now well understood,there is some controversy in metabolic diseases,so its clinical application may be limited.Microflora transplantation is recommended by clinical medical guidelines and consensus for the treatment of recurrent or refractory Clostridium difficile infection,and has been gradually promoted for the treatment of other intestinal and extraintestinal diseases.However,the initial results are varied,suggesting that the heterogeneity of the donor stools may affect the efficacy of FMT.The success of FMT depends on the microbial diversity and composition of donor feces.Therefore,clinical trials may fail due to the selection of ineffective donors,and not to faulty indication selection for FMT.A new understanding is that FMT not only improves insulin sensitivity,but may also alter the natural course of type 1 diabetes by modulating autoimmunity.In this review,we focus on the main mechanisms and deficiencies of FMT,and explore the optimal design of FMT research,especially in the field of cardiometabolic diseases.

Role of metabolites derived from gut microbiota in inflammatory bowel disease

Over the past two decades,it is improved gut microbiota plays an important role in the health and disease pathogenesis.Metabolites,small molecules produced as intermediate or end products of microbial metabolism,is considered as one of the major interaction way for gut microbiota with the host.Bacterial metabolisms of dietary substrates,modification of host molecules or bacteria are the major source of metabolites.Signals from microbial metabolites affect immune maturation and homeostasis,host energy metabolism as well as mucosal integrity maintenance.Based on many researches,the composition and function of the microbiota can be changed,which is also seen in the metabolite profiles of patients with inflammatory bowel disease(IBD).Additionally,some specific classes of metabolites also can trigger IBD.In this paper,definition of the key classes of microbialderived metabolites which are changed in IBD,description of the pathophysiological basis of association and identification of the precision therapeutic modulation in the future are the major contents.

Role of adherent invasive Escherichia coli in pathogenesis of inflammatory bowel disease

Gut microbiota imbalances play an important role in inflammatory bowel disease(IBD),but no single pathogenic microorganism critical to IBD that is specific to the IBD terminal ileum mucosa or can invade intestinal epithelial cells has been found.Invasive Escherichia coli(E.coli)adhesion to macrophages is considered to be closely related to the pathogenesis of inflammatory bowel disease.Further study of the specific biological characteristics of adherent invasive E.coli(AIEC)may contribute to a further understanding of IBD pathogenesis.This review explores the relationship between AIEC and the intestinal immune system,discusses the prevalence and relevance of AIEC in Crohn's disease and ulcerative colitis patients,and describes the relationship between AIEC and the disease site,activity,and postoperative recurrence.Finally,we highlight potential therapeutic strategies to attenuate AIEC colonization in the intestinal mucosa,including the use of phage therapy,antibiotics,and anti-adhesion molecules.These strategies may open up new avenues for the prevention and treatment of IBD in the future.