What is the effect of inflammation on intestinal function?

Impact of psychological stress on irritable bowel syndrome

Psychological stress is an important factor for the development of irritable bowel syndrome (IBS). More and more clinical and experimental evidence showed that IBS is a combination of irritable bowel and irritable brain. In the present review we discuss the potential role of psychological stress in the pathogenesis of IBS and provide comprehensive approaches in clinical treatment. Evidence from clinical and experimental studies showed that psychological stresses have marked impact on intestinal sensitivity, motility, secretion and permeability, and the underlying mechanism has a close correlation with mucosal immune activation, alterations in central nervous system, peripheral neurons and gastrointestinal microbiota. Stress-induced alterations in neuro-endocrine-immune pathways acts on the gut-brain axis and microbiota-gut-brain axis, and cause symptom flare-ups or exaggeration in IBS. IBS is a stress-sensitive disorder, therefore, the treatment of IBS should focus on managing stress and stress-induced responses. Now, non-pharmacological approaches and pharmacological strategies that target on stress-related alterations, such as antidepressants, antipsychotics, miscellaneous agents, 5-HT synthesis inhibitors, selective 5-HT reuptake inhibitors, and specific 5-HT receptor antagonists or agonists have shown a critical role in IBS management. A integrative approach for IBS management is a necessary.

Mechanisms underlying visceral hypersensitivity in irritable bowel syndrome

Visceral hypersensitivity is currently considered a key pathophysiological mechanism involved in pain perception in large subgroups of patients with functional gastrointestinal disorders, including irritable bowel syndrome (IBS). In IBS, visceral hypersensitivity has been described in 20%-90% of patients. The contribution of the central nervous system and psychological factors to visceral hypersensitivity in patients with IBS may be significant, although still debated. Peripheral factors have gained increasing attention following the recognition that infectious enteritis may trigger the development of persistent IBS symptoms, and the identification of mucosal immune, neural, endocrine, microbiological, and intestinal permeability abnormalities. Growing evidence suggests that these factors play an important role in pain transmission from the periphery to the brain via sensory nerve pathways in large subsets of patients with IBS. In this review, we will report on recent data on mechanisms involved in visceral hypersensitivity in IBS, with particular attention paid to peripheral mechanisms.

Clinical, endoscopical and morphological efficacy of mesalazine in patients with irritable bowel syndrome

Objectives:

The aim of this study was to analyze the clinical efficacy and cytomorphologic changes of colon mucosa following the treatment of patients suffering from irritable bowel syndrome (IBS) with mesalazine (5-aminosalicylic acid [5-ASA]).

Methods:

In this controlled, randomized, blind clinical trial, a total of 360 patients with varying subtypes of IBS were randomly treated with 500 mg of mesalazine qid or by standard therapy without mesalazine for a period of 28 days. Pre- and post-treatment pain intensity, pain duration, meteorism, stool abnormalities and endoscopic parameters were monitored, and biopsies or brush biopsies were examined histologically.

Results:

Treatment of IBS patients with mesalazine significantly reduced intensity and duration of pain in all subtypes of IBS, except for duration of pain in the subtype “undifferentiated”, where the difference was not significant. In addition, in patients with diarrhea type and undifferentiated type of IBS, mesalazine also significantly reduced the abnormal stool pattern. In comparison to the control group, administration of mesalazine reduced the incidence of endoscopic and cytomorphologic changes of the bowel mucosa, including changes in colon mucus, mucus production, cytologic or histologic parameters, epithelial cell degeneration, appearance of leukocytes and macrophages and cell infiltrations.

Conclusion:

Mesalazine was effective in reducing several symptoms characteristic of IBS. It significantly reduced pain intensity and duration and improved cytohistologic parameters of the bowel mucosa.

Clinical, endoscopical and morphological efficacy of mesalazine in patients with irritable bowel syndrome

OBJECTIVES

The aim of this study was to analyze the clinical efficacy and cytomorphologic changes of colon mucosa following the treatment of patients suffering from irritable bowel syndrome (IBS) with mesalazine (5-aminosalicylic acid [5-ASA]).

METHODS

In this controlled, randomized, blind clinical trial, a total of 360 patients with varying subtypes of IBS were randomly treated with 500 mg of mesalazine qid or by standard therapy without mesalazine for a period of 28 days. Pre- and post-treatment pain intensity, pain duration, meteorism, stool abnormalities and endoscopic parameters were monitored, and biopsies or brush biopsies were examined histologically.

RESULTS

Treatment of IBS patients with mesalazine significantly reduced intensity and duration of pain in all subtypes of IBS, except for duration of pain in the subtype "undifferentiated", where the difference was not significant. In addition, in patients with diarrhea type and undifferentiated type of IBS, mesalazine also significantly reduced the abnormal stool pattern. In comparison to the control group, administration of mesalazine reduced the incidence of endoscopic and cytomorphologic changes of the bowel mucosa, including changes in colon mucus, mucus production, cytologic or histologic parameters, epithelial cell degeneration, appearance of leukocytes and macrophages and cell infiltrations.

CONCLUSION

Mesalazine was effective in reducing several symptoms characteristic of IBS. It significantly reduced pain intensity and duration and improved cytohistologic parameters of the bowel mucosa.

Evidence of overlapping genetic diathesis of panic attacks and gastrointestinal disorders in a sample of male twin pairs

We explored the comorbidity between panic attacks (PA), whose symptoms can include gastrointestinal discomfort, and gastrointestinal disorders (GD). Structural equation modeling was used to analyze data from 1,874 MZ and 1,498 DZ male-male twin pairs from the Vietnam Era Twin Registry. PA and GD were associated (relative risk for GD = 2). The percentage of liability due to genetic factors was estimated to be 37% for PA and 31% for GD. There was significant correlation between the genetic risk factors for PA and GD (estimated r = .55, 95% CI of 34% to 82%) and no evidence of correlation between the environmental causes of PA and GD. Therefore, PA and GD comorbidity can be explained by overlapping genetic factors and not overlapping environmental factors. Although these data cannot identify a biological pathway for such a shared liability, it suggests the presence of GD may be informative for genetic studies of panic.