Effects of Red Wine Vinegar Beverage on the Colonic Tissue of Rodents: Biochemical, Functional and Pharmacological Analyses.

A beverage made of red wine vinegar and grape juice (Yamanashi-no-megumi™) was developed as a supplemental fluid containing polyphenols, which has been clinically shown to enhance the colonic transit. In this study, we assessed the mechanism of its prokinetic action by analyzing the effects on both the colonic phosphodiesterase activity of rats (n=4) and the isolated colonic strip preparation of guinea pigs (n=4). The 7% (v/v) solution of the beverage significantly decreased the phosphodiesterase activity by 9% (n=4). The beverage in concentrations of 0.7, 2.1 and 7% (v/v) relaxed the colonic strips pre-contracted by 1 µmol/L of carbachol in a concentration-related manner with 50, 58 and 79%, each response of which was diminished to 11, 19 and 46%, respectively in the presence of 100 µmol/L of L-nitro-arginine methyl ester. These results obtained by biochemical, functional and pharmacological analyses suggest that the beverage could relax the colon through both cAMP-associated and nitric oxide-dependent pathways, which may partly explain clinically observed prokinetic effect of the beverage.

Comparative pharmacokinetics of rhein in normal and loperamide-induced constipated rats and microarray analysis of drug-metabolizing genes.

ETHNOPHARMACOLOGICAL RELEVANCE: Rhein is a pharmacological active component found in Rheum palmatum L. that is the major herb of the San-Huang-Xie-Xin-Tang (SHXXT), a medicinal herbal product used as a remedy for constipation. Here we have investigated the comparative pharmacokinetics of rhein in normal and constipated rats. Microarray analysis was used to explore whether drug-metabolizing genes will be altered after SHXXT treatment. MATERIALS AND METHODS: The comparative pharmacokinetics of rhein in normal and loperamide-induced constipated rats was studied by liquid chromatography with electrospray ionization tandem mass spectrometry (LC-MS/MS). Gene expression profiling in drug-metabolizing genes after SHXXT treatment was investigated by microarray analysis and real-time polymerase chain reaction (RT-PCR). RESULTS: A validated LC-MS/MS method was applied to investigate the comparative pharmacokinetics of rhein in normal and loperamide-induced constipated rats. The pharmacokinetic results demonstrate that the loperamide-induced constipation reduced the absorption of rhein. Cmax significantly reduced by 2.5-fold, the AUC decreased by 27.8%; however, the elimination half-life (t1/2) was prolonged by 1.6-fold. Tmax and mean residence time (MRT) were significantly prolonged by 2.8-fold, and 1.7-fold, respectively. The volume of distribution (Vss) increased by 2.2-fold. The data of microarray analysis on gene expression indicate that five drug-metabolizing genes, including Cyp7a1, Cyp2c6, Ces2e, Atp1b1, and Slc7a2 were significantly altered by the SHXXT (0.5 g/kg) treatment. CONCLUSION: The loperamide-induced constipation reduced the absorption of rhein. Since among the 25,338 genes analyzed, there were five genes significantly altered by SHXXT treatment. Thus, information on minor drug-metabolizing genes altered by SHXXT treatment indicates that SHXXT is relatively safe for clinical application.

Decreased enteric fatty acid amide hydrolase activity is associated with colonic inertia in slow transit constipation.

BACKGROUND: Constipation is one of the most common chronic digestive complaints. Gastrointestinal transit studies have divided it into three patterns: normal transit, slow transit constipation (STC), and outlet obstruction. It has been demonstrated that STC patients respond poorly to standard therapies, and the etiology of STC remains poorly understood. Animal studies have also shown that fatty acid amide hydrolase (FAAH) controls intestinal motility through its putative receptors or non-receptor-mediated pathways. However, the role of FAAH in STC has not been elaborated. METHODS: A case series was carried out on thirty-two STC patients fulfilling the Rome II criteria and on 24 controls. All of the subjects underwent a laparotomy in Shengjing Hospital. Colonic specimens were obtained and used for FAAH expression analysis, enzyme activity assay, and cannabinoid detection. RESULTS: FAAH immunoreactivity occurred in the enteric neurons and in the surface epithelial and glands. The expression level and enzyme activity of FAAH in the STC group were both significantly lower than those in the control group (P < 0.05). The amounts of anandamide, 2-arachidonylglycerol, and palmitoylethanolamide, which are negatively correlated with enzyme activity, were significantly higher in the constipation group than that in the control group. In the STC group, cannabinoid receptor type 1 immunoreactivity occurred predominantly in the submucosal and myenteric fibers that were obviously strong and wave-like in their appearance. Enteric ganglions decreased or disappeared. CONCLUSIONS: The tone of the enteric cannabinoids system is disturbed in STC, and the decreased enteric FAAH activity contributes to colonic inertia in STC.

Emerging receptor target in the pharmacotherapy of irritable bowel syndrome with constipation.

Preclinical experiments in rodent models have recently provided new information on the mechanisms underlying pain sensation in chronic visceral hypersensitivity, as well as insights into the mechanism of action of new drugs targeting abdominal pain in irritable bowel syndrome (IBS). This article describes the evidence base supporting the role of guanylate cyclase C (GC-C) activation in the modulation of gastrointestinal transit and, in particular, in visceral hypersensitivity. We propose that GC-C activation represents an important emerging target for pharmacotherapy in IBS with constipation (IBS-C), particularly given the recent regulatory approval of the GC-C agonist linaclotide as a treatment for IBS-C. More specifically, we address the following questions: "How is pain transmitted from the colon?"; "How is abdominal pain increased in IBS-C?"; "How can we reduce IBS-related abdominal pain - what drugs have been developed?"; "Does linaclotide reduce abdominal pain in animals and humans?"; and "How does linaclotide reduce abdominal pain?".

Luminal cysteine-proteases degrade colonic tight junction structure and are responsible for abdominal pain in constipation-predominant IBS.

OBJECTIVES: Luminal serine-proteases lead to increased colonic paracellular permeability and visceral hypersensitivity in patients with diarrhea-predominant irritable bowel syndrome (IBS-D). Other proteases, namely cysteine-proteases (CPs), increase airway permeability by digesting epithelial tight junction proteins. In this study, we focused on constipation-predominant IBS (IBS-C) and we aimed to (i) evaluate CP levels in two cohorts of IBS patients, (ii) test if IBS-C fecal supernatant (FSN) affects permeability, and visceral sensitivity after repeated administrations in mice, and (iii) evaluate occludin expression in IBS-C colonic biopsies. METHODS: Fecal CP activity was determined using selective substrate and inhibitor (E64). The effect of papain, as positive control, and IBS-C FSN administrations were evaluated on colonic paracellular permeability and mucosal occludin levels in mice and T84 monolayers. Occludin protein levels were evaluated in IBS-C colonic biopsies. Sensitivity to colorectal distension (CRD) was measured after repeated administrations of IBS-C FSN. RESULTS: We found in a subset of IBS-C patients an enhanced fecal CP activity, in comparison with healthy controls and IBS-D patients. CP activity levels positively correlated with disease severity and abdominal pain scoring. This association was confirmed by receiver operating characteristic curve analysis. In mice, repeated application of IBS-C FSN into colon triggered increased permeability, linked to the enzymatic degradation of occludin, and was associated with enhanced visceral sensitivity to CRD. Finally, occludin levels were found decreased in colonic biopsies from IBS-C patients, and IBS-C FSNs were able to degrade recombinant human occludin in vitro. All these effects were abolished by preincubation of IBS-C FSN with a CP inhibitor, E64. CONCLUSIONS: These data suggest that luminal CPs may represent a new factor contributing to the genesis of symptoms in IBS.

Linaclotide, a synthetic guanylate cyclase C agonist, for the treatment of functional gastrointestinal disorders associated with constipation.

Chronic constipation (CC) and irritable bowel syndrome with constipation (IBS-C) are two functional gastrointestinal disorders that are associated with constipation. CC and IBS-C affect approximately 20% of the general population including the elderly, impairing quality of life. Patients not responding to over-the-counter treatments require effective and safe long-term therapies. Some treatments introduced in the last decade have been associated with side effects that led to withdrawal from the US market (e.g., tegaserod) or intolerance to treatment (e.g., nausea in patients treated with lubiprostone). Linaclotide is a novel drug, with a unique mechanism of action, low bioavailability and local action in the intestinal epithelial cells. It is currently being developed for patients with CC and IBS-C. From animal studies to human pharmacodynamic Phase Ib trials, and a comprehensive program of Phase IIb and III trials in health and disease, linaclotide demonstrates long-term efficacy and safety in CC and IBS-C.

[Model of gastroesophageal reflux concomitant with functional constipation in conditions of nitric oxide synthase inhibition].

Gastroesophageal reflux combined with functional constipation prevented bythe introduction of nitric oxide synthase blocker. Gastroesophageal reflux simulated by the administration of nitric oxide donor - methylene blue at fundal department of the stomach and constipation - by free ligation overlaid on the terminal division sigmoid colon of rats. The protective effect of nitric oxide synthase blocker on the gastroesophageal reflux development was demonstrated.

Abnormalities of prostaglandins and cyclooxygenase enzymes in female patients with slow-transit constipation.

BACKGROUND AND AIMS: Chronic constipation due to slow transit (STC) is more common in female than in male patients. We have previously shown that these gender differences may be due to over expression of progesterone (PG) receptors that alter G protein patterns. We sought to elucidate the mechanisms responsible for the impaired basal colonic motility in female patients with STC. METHODS: Muscle tissues from females with STC and controls with adeno-carcinoma of the colon were studied. Prostaglandins were determined by immunoassay, COX enzymes by Western blot and COX enzymes and progesterone receptors mRNA by RT-PCR. RESULTS: STC patients had impaired colonic motility index, lower TxA(2) and PGF(2) and higher PGE(2) levels than controls. STC had lower COX-1 protein and mRNA levels and higher COX-2 protein and mRNA levels than controls. These abnormalities were reproduced in normal colonic muscle cells treated with PG for 6 h. STC patients had higher PG receptor protein expression and mRNA levels than controls suggesting over expression of these receptors. CONCLUSIONS: These findings suggest that the impaired motility index of STC is due to abnormal levels of prostaglandin and COX enzymes, probably caused by an over expression of PG receptors that make muscle cells more sensitive to circulating levels of PG.

Histological studies on Hirschsprung's disease and its allied disorders in childhood.

BACKGROUND/AIMS: To obtain accurate diagnosis for Hirschsprung's disease (HD) and its allied disorders such as hypoganglionosis (Hypo) and intestinal neuronal dysplasia (IND) in childhood patients with chronic constipation, we studied the histology of childhood patients with refractory constipation accompanied by abdominal distension and pain. METHODOLOGY: Based on clinical signs and symptoms noted on admission, all of 109 patients (60 males and 49 females, aged 2-15 years with a mean age of 9.8 years) were suspected to have chronic refractory constipation. To obtain accurate histological diagnosis in childhood patients with chronic refractory constipation, we performed rectal biopsies on these patients. Tissue samples were frozen and 12-microm sections were stained with acetylcholinesterase (AChE) by the method of Karnovsky and Roots, and with nicotinamide adenine dinucleotide phosphate (NADPH)-diaphorase by the modified Scherer-Singler's method. RESULTS: On the basis of histological studies using rectal biopsies, 20 cases were diagnosed with Hypo, 5 with HD, 2 with intestinal neuronal dysplasia (IND), and 82 with normal findings. The incidence of normal cases was significantly greater than that of allied disorders of HD including both Hypo and IND (P<0.0001). The incidence of Hypo was also significantly greater than that of Hypo and IND (P<0.01, P<0.0001, respectively). Both HD and IND could be diagnosed by rectal mucosal biopsies with AChE staining. However, accurate diagnosis of Hypo could be made only through examination of the submucosal and myenteric plexuses by NADPH-diaphorase staining in full-thickness rectal specimens. CONCLUSIONS: We were able to obtain accurate diagnosis of childhood patients with HD and IND by rectal mucosal biopsy with AChE staining. On the other hand, accurate histological diagnosis in patients with Hypo could also be obtained by NADPH-diaphorase staining in full-thickness rectal specimens. That is to say, it is easier for the investigator to detect the cholinergic fiber and ganglion cell in the gut wall using NADPH-diaphorase staining than by using AChE staining.

Acetylcholinesterase distribution and refractory constipation - a new criterion for diagnosis and management.

To describe manifestations of acetylcholinesterase (AchE) activity in the bowel of patients presenting with refractory constipation and correlate them with outcome, rectal biopsy specimens (RBS) from 165 patients who presented with refractory constipation between 1988 and 1999 were examined. Age at biopsy ranged from 4 days to 17 years; 45 subjects were excluded because they satisfied diagnostic criteria for Hirschsprung's disease, intestinal neuronal dysplasia, or hypoganglionosis. Thirty-five autopsy subjects were used as controls. All RBS were compared and AchE activity was assessed in the lamina propria (LP), muscularis mucosae (MM), and around the submucosal vessels (V). Variations in AchE distribution were classified as grade I (no AchE-positive nerve fibers in the LP or MM), grade II (some positive fibers in the LP or MM), grade III (moderate positive fibers in the LP or MM), grade IV (many positive fibers in the LP, MM, or V), or grade V (fibrillar, foamy, or amorphous staining for AchE). All grade I (11/120) and V (12/120) subjects achieved normal bowel control with laxatives alone and all grade II subjects (58/120) did with laxatives and enemas. Grade III subjects (34/120) required addition of cisapride. All grade IV subjects (5/120) were unresponsive to conservative management and 4/5 were found to have a megarectum, which was treated surgically. AchE distribution correlated well with eventual outcome and requirement for surgery. AchE distribution could also be used to classify bowel motility disorders, and we suggest the term AchE-positive disease be used to describe them.

Protein kinase C activity of colonic mucosa in ulcerative colitis.

Protein kinase C (PKC) activity was measured in the inflamed colonic mucosa of 24 patients with ulcerative colitis and in the normal colonic mucosa of 10 patients with other benign diseases. The particulate fraction activity in ulcerative colitis mucosa was significantly increased compared with that of normal mucosa (320 +/- 47 versus 200 +/- 30 pmol/min/mg protein; p less than 0.05). Inflamed ulcerative colitis mucosa also showed significantly increased total PKC activity in the particulate fractions compared with normal mucosa (147 +/- 26 versus 37 +/- 8 pmol/min/mg tissue; p less than 0.05). Mucosal samples from ulcerative colitis patients were divided into 12 with mild and 12 with severe inflammation by histologic examination. The particulate PKC activity of severely inflamed mucosa was significantly lower than that of mildly inflamed mucosa (p less than 0.05). These results indicate that colonic inflammation in ulcerative colitis may be associated with altered cellular PKC activity.

Colonization and fecal enzyme activities after oral Lactobacillus GG administration in elderly nursing home residents.

This study was undertaken to investigate the effect of 2-week oral administration of a Lactobacillus-GG-fermented whey drink on fecal enzymes in elderly nursing home residents complaining of difficulties in defecation. The study was divided into three 2-week periods: baseline (2 dl placebo drink/day); Lactobacillus GG treatment (2 dl of a Lactobacillus-GG-fermented whey drink containing 10(8) cfu lactobacilli/ml); follow-up (2 dl placebo drink). Administration of the fermented whey drink resulted in colonization of feces by Lactobacillus GG in all the subjects. Glycocholic acid hydrolase activity and tryptic activity were significantly decreased at the end of the treatment period. The effect of Lactobacillus GG treatment on bowel function was less evident. Although the consistency of the stools appeared to normalize, no significant changes in the fecal frequency, weight and pH were observed. The results indicated that a Lactobacillus-GG-fermented whey drink can change the bacterial metabolism, and has no significant effect on bowel function.

Acetylcholinesterase and manometry in the diagnosis of the constipated child.

We studied 309 constipated infants and children who underwent rectal manometry (n = 261) and/or punch rectal biopsy, in which acetylcholinesterase histochemistry (n = 124) was compared with routine histologic examination (n = 93) for diagnostic accuracy. A 99% diagnostic accuracy was achieved with acetylcholinesterase histochemistry compared with 61% accuracy with routine hematoxylin-eosin staining on punch rectal biopsy. We recommend screening cooperative, quiet patients with rectal manometry. Most patients with abnormal manometric studies or those on whom manometry cannot be performed should have superficial punch biopsy (except those ill infants who require urgent operative intervention). This plan of management provides the least invasive but the most accurate evaluation of the constipated child. Deep rectal biopsy can be avoided except in the very rare child with hypoganglionosis or "skip-area" aganglionosis, which can be detected by manometry.

[Tryptic and chymotryptic activity in the faeces of children of different age groups (author's transl)]. / Tryptische und chymotryptische Aktivität im Stuhl von Kindern verschiedener Altersgruppen

Measurement of tryptic and chymotryptic activity in the faeces was not disturbed by bacterial proteolytic activity of different bacteria such as proteus, pseudomonas, coli, enterococci, bacteroides. Both activities within a group follow a logarithmic normal distribution. Lower limit of the standard deviation is 51% upper limit 129% for tryptic activity, respectively 60 and 170% for chymotryptic activity. There were no differences in chymotryptic activity between the 10 age groups comprising 157 healthy children, whereas a significant difference could be found for tryptic activity between premature and older children. Daily fluctuations of the enzyme activities are quite high in the same individual, and only reduced in "bottlefed" infants with constant nutrition. In prematures and very young infants chymotryptic activity predominates, later tryptic activity. Influence of increased and decreased bowel movements on deviation of the data was tested. There was, however, no real alteration of enzyme activity due to the bowel dysfunction beyond the standard deviation of the control groups. But passage time and nutrition have to be considered beside other factors in the wide distribution of the enzyme activities and the latter limits the value of this method.