Prostaglandins and serotonin in diarrheogenic syndromes

Correlation of menstrual distress to severity of gastrointestinal symptoms in inflammatory bowel disease patients

Inflammatory bowel diseases (IBD), namely, Crohn's disease (CD) and ulcerative colitis (UC) are idiopathic chronic, relapsing, inflammatory diseases of the gastrointestinal (GI) tract. Triggers for disease flares include medications, infection, acute stress, and the menstrual cycle. Varying ovarian hormone levels i.e. prostaglandins and progesterone may exaggerate GI symptoms in IBD. We aimed to determine the relationship between quality of life, endoscopic and clinical disease activity and the menstrual cycle among females with IBD through a questionnaire based cross-sectional study. The first 75 women of child-bearing age seen at IBD clinic completed a questionnaire incorporating the short IBD questionnaire (SIBDQ). Menstrual symptoms were evaluated using the validated Moos Menstrual Distress Questionnaire (MDQ) to measure cyclical peri-menstrual symptoms. Endoscopic disease severity was assessed using the Rutgeert's score (post ileo-cecal resection patients) or Simple Endoscopic Score for CD and the Mayo score for UC. There was a statistically negative correlation between MDQ and SIBDQ scores (p<0.001); i.e. patients with lower menstrual distress scores had better quality of life. We found no correlation between the SIBDQ, MDQ and endoscopic scores (p = 0.094, 0.626 respectively). Previous studies suggest that the severity of menstrual symptoms correlate with a poorer quality of life among women with IBD. However, this may not be reflective of the endoscopic disease severity. Larger studies are necessary to evaluate adjusting medication closer to menstrual period and adding supportive therapy peri-menstrually in anticipation of symptoms.

The Influence of Hormonal Fluctuation on Inflammatory Bowel Disease Symptom Severity-A Cross-Sectional Cohort Study

BACKGROUND

Many women with inflammatory bowel disease (IBD) report changes in symptoms in association with hormonal changes during menses, pregnancy, and hormonal contraceptive use, suggesting a hormonal influence on disease activity. We aimed to identify and characterize IBD symptom fluctuations in women during times of hormonal variation.

METHODS

From June 2012 through September 2012, women enrolled in Crohn's and Colitis Foundation of America Partners , an online Internet cohort of patients with IBD, were invited to participate in this study. Using a 5-point Likert scale, participants were asked to rate symptom changes during their menstrual cycle, pregnancy, the postpartum period, and after menopause. Clinical and demographic differences were assessed using univariate and multivariable methods.

RESULTS

A total of 1,203 female patients with Crohn's disease (CD) and ulcerative colitis (UC) participated (64% CD, 34% UC). Over half of the women with IBD reported worsening symptoms during menses. Symptom changes were similar between women with CD vs UC, except in pregnancy, where symptom worsening during pregnancy was more commonly seen in UC than CD (P = 0.02). Overall, women reporting symptom worsening were younger at the time of IBD diagnosis (P < 0.01), had lower quality of life (SIBDQ) scores (P < 0.01), and had a higher BMI (25 vs 24) than women without symptom worsening.

CONCLUSIONS

Women with IBD report changes in symptom severity during times of hormone fluctuation. Further clarification of the role of hormones in IBD is warranted in order to understand these relationships and to identify potential management strategies for women with IBD and hormonally sensitive gastrointestinal symptoms.

Enteric neuroimmunophysiology and pathophysiology

Minute-to-minute behavior of the bowel, whether it is normal or disordered, is determined by integrative functions of the enteric nervous system (ENS). Information input processed by the ENS is derived from local sensory receptors, the central nervous system, and immune/inflammatory cells including mast cells. Enteric mast cells use the power of the immune system for detection of antigenic threats and for long-term memory of the identity of the specific antigens. Specific antibodies attach to the mast cells and enable the mast cell to detect sensitizing antigens when they reappear in the gut lumen. Should the sensitizing antigen reappear, mast cells detect it and signal its presence to the ENS. The ENS interprets the mast cell signal as a threat and calls up from its program library secretory and propulsive motor behavior that is organized to eliminate the threat rapidly and effectively. Operation of the alarm program protects the individual, but at the expense of symptoms that include cramping abdominal pain, fecal urgency, and diarrhea. Enteric mast cells use immunologic memory functions to detect foreign antigens as they appear and reappear throughout the life of the individual. Mast cells use paracrine signaling for the transfer of chemical information to the neural networks of the ENS. Integrative circuits in the ENS receive and interpret the chemical signals from the mast cells. Signals from the mast cells are interpreted by the ENS as a labeled code for the presence of a threat in the intestinal lumen.

Morphologic patterns and diagnostic criteria of VIP-producing endocrine tumors. A histologic, histochemical, ultrastructural, and biochemical study of 32 cases

Thirty-two tumors (31 pancreatic and one jejunal) all associated with severe watery diarrhea, increased VIP levels in blood and most with hypokalemia, were investigated. The VIP content of tumor tissue ranged from 23 to 15,000 pmol/g. VIP immunoreactive cells were detected histochemically in 24 of 28 tumors investigated, PP immunoreactive cells in 11 of 28 tumors, hCG (alpha chain) immunoreactive cells in 12 of 25 tumors, and neuron specific enolase (NSE) immunoreactive cells in 24 of 26 tumors (the 2 negative results were due to inadequate fixation). All cases showed light microscopic features of epithelial endocrine tumors. Electron microscopy demonstrated a prevalence of agranular, poorly granulated and a minority of well granulated cells. Most secretory granules were round, small (150+/- 30 nm diameter) and of moderate electron density, resembling those of the so-called D1 cells. By electron immunocytochemistry, PP was directly localized in a subpopulation of relatively larger granules (154 +/- 22 nm core diameter) showing closely applied membranes. VIP-storing granules, directly identified only in the jejunal tumor, appear to correspond to a subpopulation of slightly smaller P-type granules (126 +/- 37 nm core diameter) showing a narrow, clear halo. The origin, behavior, and diagnostic criteria of VIPomas are discussed.

Prostaglandins and serotonin: nonpeptide diarrheogenic hormones

Prostaglandins and serotonin are vasoactive compounds with profound effects on the gastrointestinal tract. Both cause inhibition of gastric acid secretion (although serotonin stimulates gastric pepsin secretion), stimulation of intestinal motility, and conversion of small intestinal mucosa from absorption to secretion of water and electrolytes. Their effects on pancreatic and biliary function are still not clear. Although prostaglandins appear to elicit their effects primarily by a paracrine mode of action, and serotonin is primarily a neurotransmitter (neurocrine), it is clear that even under normal conditions both can function as humoral agents. For example, we have shown that serotonin plays a physiologic role as a humoral inhibitor of gastric acid secretion. However, the effects of these agents become more pronounced in patients with humorally mediated diarrheogenic syndromes. Serotonin (and related indoles, particularly 5-hydroxytryptophan) has been firmly implicated as a cause of diarrhea in patients with carcinoid syndrome; our recent studies suggest that the diagnosis can be more effectively made by measuring circulating immunoreactive serotonin concentrations than urinary excretion of 5-HIAA; that some circulating serotonin escapes hepatic inactivation and, thus, large intestinal tumors can cause carcinoid syndrome in the absence of hepatic metastases; and that large amounts of serotonin are produced by some noncarcinoid diarrheogenic tumors, including medullary carcinomas of the thyroid and tumors associated with the WDHA syndrome. A large number of tumors of probable neural crest origin, including medullary thyroid carcinoma, carcinoids, and tumors associated with the WDHA syndrome, secrete large amounts of prostaglandins, particularly PGE2. The clinical response of at least some of the patients harboring these tumors to inhibitors of prostaglandin synthesis (particularly indomethacin) suggests that prostaglandins play a role in the etiology of these diarrheogenic syndromes.