Efficacy of ramosetron in the treatment of male patients with irritable bowel syndrome with diarrhea: a multicenter, randomized clinical trial, compared with mebeverine

BACKGROUND

The 5-HT(3) receptor antagonists are known to be effective for the treatment of diarrhea-predominant irritable bowel syndrome (IBS), but not widely used yet. The aim of this study was to compare the efficacy and safety of ramosetron, a 5-HT(3) receptor antagonist, and mebeverine in male patients with IBS with diarrhea (IBS-D).

METHODS

This study was performed in a multicenter, randomized, open-label design. Data of 343 male patients with IBS-D who were randomized to either a 4-week treatment of ramosetron 5μg once daily or a 4-week treatment of mebeverine 135 mg three times daily were analyzed by the intent-to-treat analysis. The primary efficacy parameter was the proportion of patients with adequate relief of IBS symptoms at the last week of treatment. The secondary endpoints were changes in each symptom score and the safety profiles.

KEY RESULTS

The responder rates for global IBS symptoms, abdominal pain/discomfort and abnormal bowel habits in the ramosetron and mebeverine groups significantly increased during the treatment period. The severity scores of abdominal pain/discomfort and urgency, the stool form score, and the stool frequency in both treatment arms were significantly reduced, compared with the baselines. There were no significant differences in the responder rates (37%vs 38% on ITT analysis) and adverse event profiles between the ramosetron and mebeverine groups. Neither severe constipation nor ischemic colitis was reported by ramosetron-treated patients.

CONCLUSIONS & INFERENCES

Ramosetron 5μg once daily is as effective as mebeverine three times daily in male patients with IBS-D.

Molecular cloning of a novel pathogen-inducible cDNA encoding a putative acyl-CoA synthetase from Capsicum annuum L

By means of differential display, a pool of salicylic acid (SA)-induced mRNAs were identified and subsequently their cDNAs were isolated from a cDNA library prepared from SA-induced leaf tissues of hot pepper. One of these cDNA clones, designated CaSIG4, was 1900 bp and contained an open reading frame encoding 523 amino acids with a calculated molecular mass of 56.3 kDa. The predicted amino acid sequence of CaSIG4 showed high sequence similarity to the AMP-binding protein family of both prokaryotic and eukaryotic acyl-CoA synthetases. CaSIG4 transcripts accumulated rapidly after SA treatment and in response to both incompatible and compatible interactions with Xanthomonas campestris pv. vesicatoria race 1. To investigate the cis-acting elements mediating CaSIG4 expression, the CaSIG4 5'-flanking region was isolated by inverse PCR. Database searches indicated that a potential cis-regulatory element is almost identical to the consensus core sequences ACC(A/T)ACC(A/C) which are conserved among promoters of other phenylpropanoid biosynthetic genes. The subcellular localization of the CaSIG4 protein was studied by using a soluble modified GFP gene fusion delivered into epidermal cells of onion by biolistic bombardment. The CaSIG4-smGFP fusion protein was localized to the plasma membrane. Taken together, CaSIG4 encoding a putative acyl-CoA synthetase could function as a plasma membrane-bound protein with a role in signaling in plant defense.