Anna Mokrowiecka

Experimental colitis in mice is attenuated by changes in the levels of endocannabinoid metabolites induced by selective inhibition of fatty acid amide hydrolase (FAAH)

BACKGROUND AND AIMS Pharmacological treatment and/or maintenance of remission in inflammatory bowel diseases (IBD) is currently one of the biggest challenge in the field of gastroenterology. Available therapies are mostly limited to overcoming the symptoms, but not the cause of the disease. Recently, the endocannabinoid system has been proposed as a novel target in the treatment of IBD. Here we aimed to assess the anti-inflammatory action of the novel fatty acid amide hydrolase (FAAH) inhibitor PF-3845 and its effect on the endocannabinoid and related lipid metabolism during the course of experimental colitis. METHODS We used two models of experimental colitis in mice (TNBS- and DSS-induced) and additionally, we employed LC/MS/MS spectrometry to determine the changes in biolipid levels in the mouse colon during inflammation. RESULTS We showed that the FAAH inhibitor PF-3845 reduced experimental TNBS-induced colitis in mice and its anti-inflammatory action is associated with altering the levels of selected biolipids (arachidonic and oleic acid derivatives, prostaglandins and biolipids containing glycine in the mouse colon). CONCLUSIONS We show that FAAH is a promising pharmacological target and the FAAH-dependent biolipids play a major role in colitis. Our results highlight and promote therapeutic strategy based on targeting FAAH-dependent metabolic pathways in order to alleviate intestinal inflammation.

Transient receptor potential vanilloid 4 blockade protects against experimental colitis in mice: a new strategy for inflammatory bowel diseases treatment?

Recent reports suggested that the activation of Transient Receptor Potential Vanilloid 4 (TRPV4) receptors in the gastrointestinal tract has pro‐inflammatory effects. In this study, we demonstrated for the first time that TRPV4 mRNA expression is up‐regulated in patients with inflammatory bowel diseases (IBD). Furthermore, selective blockade of TRPV4 in the 2,4,6‐trinitrobenzenesulfonic acid animal model alleviates colitis and pain associated with the intestinal inflammation. Our study indicates that TRPV4 may play a role in mechanisms of defense in intestinal inflammation and that TRPV4 may be an attractive target for future systemic or topic anti‐inflammatory treatment in patients with IBD.

Clinical, emotional and social factors associated with quality of life in chronic pancreatitis.

Background: In chronic pancreatitis (CP), a debilitating, progressive and incurable disease, patients’ wellbeing is considerably impaired, but the different factors affecting quality of life (QoL), have not been identified yet. Methods: 69 patients with CP were evaluated (M/F 55/14; mean age 46.6 ± 10.05 years). Different degrees of pancreatic damage were defined using the Cambridge classification; pain intensity and frequency were assessed using pain index. QoL was measured using EORTC QLQ-C30 and the PAN26 questionnaire. Although developed for pancreatic cancer, the C30/PAN26 has been validated for chronic pancreatitis. Results: Digestive symptoms, financial difficulties, fear of future health and general pain scales showed considerable effects of CP on QoL. We observed significant negative correlation between mean QoL scores and pain index in almost all domains (p < 0.001, p < 0.05). Pain intensity affects QoL scales more often than pain frequency. BMI correlated positively with QoL in global health status, altered bowel habits, body image and satisfaction with health care domains (p < 0.01, p < 0.05). Conclusion: Pain index, BMI, Cambridge classification and disease duration are the most important factors adversely affecting QoL in CP. Measurement of QoL is essential in the disease management and improves the knowledge of psychosocial functioning of these patients.

Circulating Levels of Visfatin, Resistin and Pro-Inflammatory Cytokine Interleukin-8 in Acute Pancreatitis

Background: Resistin and visfatin, hormones produced by adipose tissue, have pro-inflammatory potential; however, their role in acute pancreatitis (AP) has been investigated only rarely. Methods: The study group comprised 32 patients with alcoholic AP and 30 controls. In all cases AP was classified as C according to Balthazar’s CT score and as severe according to Ranson’s criteria. The serum level of visfatin, resistin, and interleukin(IL)-8 immunoassays were measured by ELISA on admission and on the third and fifth day of hospitalization. Results: On the admission day serum resistin and IL-8 concentrations in AP patients were significantly higher than in controls and they further increased on the third and fifth day of hospitalization. On the admission day serum visfatin levels in AP patients were significantly higher than in controls and further increased on the third day of hospitalization. On the fifth day the levels decreased; however, they were still higher than on admission. The correlation between visfatin and resistin as well as between C-reactive protein and visfatin, resistin and IL-8 levels has been found. Conclusion: In the course of AP, visfatin and resistin levels increase in parallel with C-reactive protein. We speculate that those parameters may provide an additional tool for the prognosis and monitoring of AP.

Endocannabinoid and Cannabinoid-Like Fatty Acid Amide Levels Correlate with Pain-Related Symptoms in Patients with IBS-D and IBS-C: A Pilot Study

Aims Irritable bowel syndrome (IBS) is a functional gastrointestinal (GI) disorder, associated with alterations of bowel function, abdominal pain and other symptoms related to the GI tract. Recently the endogenous cannabinoid system (ECS) was shown to be involved in the physiological and pathophysiological control of the GI function. The aim of this pilot study was to investigate whether IBS defining symptoms correlate with changes in endocannabinoids or cannabinoid like fatty acid levels in IBS patients. Methods AEA, 2-AG, OEA and PEA plasma levels were determined in diarrhoea-predominant (IBS-D) and constipation-predominant (IBS-C) patients and were compared to healthy subjects, following the establishment of correlations between biolipid contents and disease symptoms. FAAH mRNA levels were evaluated in colonic biopsies from IBS-D and IBS-C patients and matched controls. Results Patients with IBS-D had higher levels of 2AG and lower levels of OEA and PEA. In contrast, patients with IBS-C had higher levels of OEA. Multivariate analysis found that lower PEA levels are associated with cramping abdominal pain. FAAH mRNA levels were lower in patients with IBS-C. Conclusion IBS subtypes and their symptoms show distinct alterations of endocannabinoid and endocannabinoid-like fatty acid levels. These changes may partially result from reduced FAAH expression. The here reported changes support the notion that the ECS is involved in the pathophysiology of IBS and the development of IBS symptoms.

Anti-Inflammatory and Antinociceptive Action of an Orally Available Nociceptin Receptor Agonist SCH 221510 in a Mouse Model of Inflammatory Bowel Diseases

The nociceptin receptors (NOPs) are expressed in the gastrointestinal (GI) tract on muscle cell membranes and neurons, as well as the immune cells that infiltrate the mucosa. The involvement of NOPs in the pathophysiology of GI inflammation has been suggested, but due to the lack of selective NOP agonists, it never fully elucidated. Our aim was to characterize the anti-inflammatory and antinociceptive effect of the NOP agonist, SCH 221510 [3-endo-8-[bis(2-methylphenyl)methyl]-3-phenyl-8-azabicyclo [3.2.1]octan-3-ol], as a potential therapeutic strategy in the treatment of inflammatory bowel diseases (IBD). The anti-inflammatory action of SCH 221510 was determined after intraperitoneal, oral, and intracolonic administration of SCH 221510 (0.1–3.0 mg/kg once or twice daily) in mice treated with 2,4,6-trinitrobenzenesulfonic acid (TNBS). Antinociceptive action of SCH 221510 was evaluated in the mouse model of mustard oil (MO)-induced abdominal pain. Relative NOP mRNA expression was assessed in patients with IBD using real-time reverse transcriptase-polymerase chain reaction. We found that the expression of NOP mRNA was significantly decreased in patients with IBD. The administration (0.1 and 1.0 mg/kg i.p. twice daily and 3 mg/kg p.o. twice daily) of SCH 221510 attenuated TNBS colitis in mice. This effect was blocked by a selective NOP antagonist [J-113397 [(±)-1-[(3R*,4R*)-1-(cyclooctylmethyl)-3-(hydroxymethyl)-4-piperidinyl]-3-ethyl-1,3-dihydro-2H-benzimidazol-2-one]]. The intracolonic injections of SCH 221510 did not improve colitis in mice. The antinociceptive effect of SCH 221510 was observed after oral administration of SCH 221510 in MO-induced pain tests in mice with acute colitis. In conclusion, our results show a potent anti-inflammatory and antinociceptive effect upon selective activation of NOP receptors and suggest that the NOP agonist SCH 221510 is a promising drug candidate for future treatment of IBD.

p16 gene mutations in Barrett's esophagus in gastric metaplasia – intestinal metaplasia – dysplasia – adenocarcinoma sequence

PURPOSE Barretts associated esophageal adenocarcinoma (ADC) is one of the malignancies of most rapidly increasing incidence. The aim of the study was to assess p16 tumor suppressor gene alterations in the ADC premalignant conditions. MATERIAL & METHODS In the present study two p16 gene mutations (A148T and I49S) analysis with PCR- RFLP method have been performed in oesophageal biopsy specimen in 33 patients with Barretts gastric metaplasia (GM), 27 - with Barretts intestinal metaplasia (IM), 8 - with dysplasia and 11 - with ADC. RESULTS We have detected the I49S mutation in 12% (4/33) patients with GM, 18% (5/27) with IM, 50% - with dysplasia (4/8) and in 27% (3/11) - with ADC. The A148T mutation were found in 3% (1/33) patients with GM, 22% (6/27) - IM, 25% (2/8) - dysplasia and 27% patients with ADC (3/11). The frequency of the A148S mutation was rising in GM - IM - dysplasia - ADC sequence and was significantly lower in GM compared to all other grades taken together (p=0.0256). The frequency of the I49S mutation was rising in GM - IM - dysplasia sequence, to drop in ADC cases. There were no significant differences in frequency of the I49S mutation between studied groups. CONCLUSIONS These findings are consistent with the hypothesis on the role of the p16 mutations in early phase of Barretts epithelium progression to ADC. The presence of p16 mutations in esophageal metaplastic columnar epithelium without goblet cells suggest that this pathology may have malignancy potential.

Orally administered novel cyclic pentapeptide P-317 alleviates symptoms of diarrhoea-predominant irritable bowel syndrome.

The aim of our study was to characterize the effect of P‐317, a novel cyclic derivative of morphiceptin, on gastrointestinal (GI) motility and abdominal pain in mouse models mimicking symptoms of diarrhoea‐predominant irritable bowel syndrome (IBS‐D).

Anti-inflammatory action of a novel orally available peptide 317 in mouse models of inflammatory bowel diseases

BACKGROUND The endogenous opioid system constitutes an attractive target in the treatment of GI disorders, including inflammatory bowel diseases (IBD). The aim of our study was to characterize the anti-inflammatory and antinociceptive effect of P-317, a novel cyclic analog of opioid peptide morphiceptin, in animal models of IBD. METHODS The anti-inflammatory effect of P-317 after intraperitoneal (ip) and oral (po) administration was assessed in two mouse models of IBD - Crohns disease, induced by intracolonic instillation of trinitrobenzenesulfonic acid (TNBS) and ulcerative colitis, induced by addition of dextran sodium sulfate (DSS) into drinking water. The antinociceptive action of P-317 was characterized in mice with acute colitis using mustard oil-induced pain test. Real time RT PCR was used to assess semiquantitatively the expression of IL-1β and TNF-α mRNA in mouse colonic samples. To translate our results to clinical conditions, MOP and KOP mRNA were quantified in human colonic biopsies from IBD patients. RESULTS P-317 (0.1mg/kg, ip and 1mg/kg, po) alleviated colonic inflammation in TNBS- and DSS-treated mice in the opioid receptor-dependent manner. The anti-inflammatory effect of P-317 was associated with the decrease in mRNA expression of proinflammatory cytokines. The antinociceptive effect of P-317 was observed after ip and po administration in mice with acute colitis. CONCLUSION Our results show a potent anti-inflammatory and antinociceptive effect of P-317 in mouse models of colitis upon activation of opioid receptors. The unique bioavailability of P-317 after oral administration suggests that it is a promising drug candidate for future treatment of IBD.

Activation of the endogenous nociceptin system by selective nociceptin receptor agonist SCH 221510 produces antitransit and antinociceptive effect: a novel strategy for treatment of diarrhea-predominant IBS

Diarrhea‐predominant irritable bowel syndrome (IBS‐D) is a functional gastrointestinal (GI) disorder, defined by the presence of loose stools and abdominal pain. In search for a novel anti‐IBS‐D therapy, here we investigated the nociceptin receptor (NOP)‐dependent effects in the GI tract.