加载中

    logo
    The pros, cons, and many unknowns of probiotics. Suez Jotham,Zmora Niv,Segal Eran,Elinav Eran Nature medicine Consumption of over-the-counter probiotics for promotion of health and well-being has increased worldwide in recent years. However, although probiotic use has been greatly popularized among the general public, there are conflicting clinical results for many probiotic strains and formulations. Emerging insights from microbiome research enable an assessment of gut colonization by probiotics, strain-level activity, interactions with the indigenous microbiome, safety and impacts on the host, and allow the association of probiotics with physiological effects and potentially useful medical indications. In this Perspective, we highlight key advances, challenges and limitations in striving toward an unbiased interpretation of the large amount of data regarding over-the-counter probiotics, and propose avenues to improve the quality of evidence, transparency, public awareness and regulation of their use. 10.1038/s41591-019-0439-x
    The influence of the brain-gut axis in inflammatory bowel disease and possible implications for treatment. Gracie David J,Hamlin P John,Ford Alexander C The lancet. Gastroenterology & hepatology Brain-gut interactions affect psychological wellbeing and symptom reporting in functional gastrointestinal disorders; the presence of anxiety or depression is associated with the development of new-onset gastrointestinal symptoms, and the presence of gastrointestinal symptoms is associated with the development of psychological disorders de novo. In inflammatory bowel diseases (IBD), the reporting of irritable bowel syndrome (IBS)-type symptoms by patients with quiescent disease is common, and is associated with psychological disorders, impaired quality of life, and increased health-care use. In IBD, data from observational studies suggest that psychological disorders might be associated with relapse of disease activity, and that inflammatory activity is associated with the development of new psychological disorders, as has been described for functional gastrointestinal disorders such as IBS and functional dyspepsia. The brain-gut axis provides the physiological link between the CNS and gastrointestinal tract that might facilitate these relationships. In IBS, treatments targeting disordered brain-gut axis activity, including psychological therapies and antidepressants, might lead to improved symptoms and quality of life. However, in IBD, the benefit of these treatments is less certain because of a scarcity of interventional studies. Despite the scarcity of trials, observational data suggest that the effect of disordered brain-gut axis activity in IBD is substantial, and scope remains for further well designed trials of psychological therapies and antidepressants, particularly in the subset of patients who have coexistent psychological disorders, or in those who report IBS-type symptoms. Integrating these treatments into a biopsychosocial model of care has the potential to improve both psychological wellbeing and quality of life in some patients with IBD, reducing health-care use and altering the natural history of disease. 10.1016/S2468-1253(19)30089-5
    The role of mast cells in functional GI disorders. Wouters Mira M,Vicario Maria,Santos Javier Gut Functional gastrointestinal disorders (FGIDs) are characterized by chronic complaints arising from disorganized brain-gut interactions leading to dysmotility and hypersensitivity. The two most prevalent FGIDs, affecting up to 16-26% of worldwide population, are functional dyspepsia and irritable bowel syndrome. Their etiopathogenic mechanisms remain unclear, however, recent observations reveal low-grade mucosal inflammation and immune activation, in association with impaired epithelial barrier function and aberrant neuronal sensitivity. These findings come to challenge the traditional view of FGIDs as pure functional disorders, and relate the origin to a tangible organic substrate. The mucosal inflammatory infiltrate is dominated by mast cells, eosinophils and intraepithelial lymphocytes in the intestine of FGIDs. It is well established that mast cell activation can generate epithelial and neuro-muscular dysfunction and promote visceral hypersensitivity and altered motility patterns in FGIDs, postoperative ileus, food allergy and inflammatory bowel disease. This review will discuss the role of mucosal mast cells in the gastrointestinal tract with a specific focus on recent advances in disease mechanisms and clinical management in irritable bowel syndrome and functional dyspepsia. 10.1136/gutjnl-2015-309151
    Management of the multiple symptoms of irritable bowel syndrome. Simrén Magnus,Törnblom Hans,Palsson Olafur S,Whitehead William E The lancet. Gastroenterology & hepatology Irritable bowel syndrome (IBS) is one of the most common functional gastrointestinal disorders. A stepwise management approach is advocated for patients with IBS. For a substantial proportion of patients with mild symptoms, general management principles, including making a confident diagnosis and offering explanation, reassurance, and dietary and lifestyle advice, are sufficient. However, many patients continue to have moderate-to-severe symptoms and are not satisfied solely with this approach. In these patients, use of pharmacotherapy on the basis of the predominant symptom (constipation, diarrhoea, pain, or bloating) or combination of symptoms is the next step. For patients with symptoms that are refractory to these initial treatment options and those who have comorbid conditions or psychological symptoms, a combination of therapies should be used, and the use of psychotropic drugs and psychological treatment alternatives is often effective. Finally, the key to successful treatment of patients with IBS is a good physician-patient relationship and use of person-centred care principles. 10.1016/S2468-1253(16)30116-9
    Pathophysiology of irritable bowel syndrome. Holtmann Gerald J,Ford Alexander C,Talley Nicholas J The lancet. Gastroenterology & hepatology Traditionally, irritable bowel syndrome has been considered to be a disorder with no known underlying structural or biochemical explanation, but this concept is likely to be outdated. In this Review we challenge the widely accepted view that irritable bowel syndrome is an unexplained brain-gut disorder. There is epidemiological evidence that, in a major subset of patients, gastrointestinal symptoms arise first and only later do incident mood disorders occur. Additionally, possible mechanisms for gut-brain dysfunction have been identified, suggesting primary gut disturbances might be the underlying cause in a subgroup. Underlying mechanisms that could lead to irritable bowel syndrome include genetic factors (most notably an identified mutation of SCN5A); post-infectious changes, chronic infections and disturbances in the intestinal microbiota; low-grade mucosal inflammation, immune activation, and altered intestinal permeability; disordered bile salt metabolism (in 10-20% of cases with diarrhoea); abnormalities in serotonin metabolism; and alterations in brain function, which could be primary or secondary factors. Identical irritable bowel syndrome symptoms are probably due to different disease processes; grouping patients with this disorder into either diarrhoea-predominant or constipation-predominant subtypes promotes heterogeneity. An approach based on the underlying pathophysiology could help to develop therapies that target causes and ultimately provide a cure for patients with irritable bowel syndrome. 10.1016/S2468-1253(16)30023-1