Enteric glial cells and their role in gastrointestinal motor abnormalities: Introducing the neuro-gliopathies

The role of enteric glial cells has somewhat changed from that of mere mechanical support elements, gluing together the various components of the enteric nervous system, to that of active participants in the complex interrelationships of the gut motor and inflammatory events. Due to their multiple functions, spanning from supporting elements in the myenteric plexuses to neurotransmitters, to neuronal homeostasis, to antigen presenting cells, this cell population has probably more intriguing abilities than previously thought. Recently, some evidence has been accumulating that shows how these cells may be involved in the pathophysiological aspects of some diseases. This review will deal with the properties of the enteric glial cells more strictly related to gastrointestinal motor function and the human pathological conditions in which these cells may play a role, suggesting the possibility of enteric neuro- gliopathies.

Gastrointestinal motility disorders in inflammatory bowel diseases

The relationship between motility and inflammatory gastrointestinal disorders is at the same time complex and intriguing since these conditions might share some genetic,environmental,immunological and microbial predisposing factors.In addition,significant symptom overlapping may occur,muddling the waters within the clinical context.Although on one hand this represents a challenge for the clinician for a potential under-or over-treatment and diagnostic delay,on the other hand it possibly represents an opportunity for the researcher to better disclose the intimate relationship between chronic(often low-grade)inflammation,motor disorders and deranged sensory function.The best example is probably represented by Crohn’s disease and ulcerative colitis.In fact,a number of gastrointestinal motor disorders have been described in association with these diseases,disorders which span from the esophagus to the anorectum,and which will be extensively covered in this review.It is conceivable that at least part of this derangement is strictly related to inflammatory cytokine trafficking and neuromuscular changes;however,given the high prevalence of functional gastrointestinal disorders in the general population,this overlap might also be serendipitous.However,it is worth noting that literature data on this topic are relatively scarce,sometimes quite outdated,and mostly focused on the interplay between irritable bowel syndrome and inflammatory bowel disease.Nevertheless,both researchers and clinicians must be aware that symptoms related to gastrointestinal motility disorders may be highly prevalent in both active and inactive inflammatory bowel disease,correlate with greater psychological comorbidity and poorer quality of life,and may negatively influence the therapeutic approaches.

Novel oral-targeted therapies for mucosal healing in ulcerative colitis

Ulcerative colitis(UC), a chronic, relapsing, remitting disease of the colon and rectum, is characterized by inflammatory ulceration of the mucosa. Current UC therapy relies on controlling acute episodes and preventing relapse. To predict modifications in the natural course of UC, mucosal healing(MH) has emerged as a major treatment goal. Endoscopic evaluation is considered the gold standard for assessing MH, which can be achieved by conventional drugs and biologics in many, but not all, patients. Consequently, interest is focusing on the development of new substances for UC therapy, and new oral agents are in the pipeline. This review will focus on the ability of newly developed oral drugs to induce and maintain MH in UC patients.

Histological healing in inflammatory bowel disease:A still unfulfilled promise

Treatment of inflammatory bowel disease(IBD) is traditionally based on several drugs,including salicylates,corticosteroids,and antibiotics;in addition,the therapeutic armamentarium has considerably evolved with the advent of newer,effective therapeutic measures(such as the biological agents) that are able to improve in a considerable manner both the clinical and endoscopic variables.Thus,mucosal healing,at least considered from an endoscopic point of view,is today regarded as the ultimate endpoint for treatment of these conditions.However,it is also increasingly clear that endoscopic healing is not necessarily paralleled by histological healing;There are few doubts that the latter should be considered as a true,objective healing and the ultimate goal to reach when treating patients with IBD.Unfortunately,and surprisingly,only a few,incomplete,and somewhat conflicting data exist on this topic,especially because there is still the need to standardize both histological assessment and the severity grading of these disorders;Issues that have not been yet been resolved for clinical practice and therapeutic trials.Hopefully,with the help of an increased awareness on the clinical researchers' side,and the availability of dedicated pathologists on the other side,this matter will be effectively faced and resolved in the near future.

Inflammatory bowel disease in the dog:Differences and similarities with humans

Inflammatory bowel diseases (IBD) represent important chronic conditions affecting the gastrointestinal tract in man.However,similar disorders are found in several animal species and the IBD affecting dogs are particularly important.These are encompassed by an umbrella of probably several different entities with common symptoms,some of which seem to share striking similarities with human conditions.This review will focus on the actual knowledge of IBD in dogs,and attempt to identify differences and similarities with human IBD conditions.