Dietary guidance normalizes large intestinal endocrine cell densities in patients with irritable bowel syndrome.

BACKGROUND/OBJECTIVES: To determine the large intestinal endocrine cell types affected following dietary guidance in patients with irritable bowel syndrome (IBS). SUBJECTS/METHODS: The study included 13 IBS patients and 13 control subjects. The patients received three sessions of individualized dietary guidance. Both the control subjects and the patients were scheduled for colonoscopies at baseline and again for the patients at 3-9 months after dietary guidance. Biopsy samples were taken from the colon and rectum and were immunostained for all types of large intestinal endocrine cells. The endocrine cells were quantified using computerized image analysis. RESULTS: The daily total consumption (mean±s.e.m. values) of fruits and vegetables rich in FODMAPs (fermentable oligosaccharides, disaccharides, monosaccharides and polyols) decreased significantly from 16.2±5.3 g before receiving dietary guidance to 9.2±3.2 g after receiving dietary guidance (P=0.02). In the total colon, the densities of serotonin cells were 46.8±8.9, 10.5±2.1 and 22.6±3.2 cells/mm(2) in control subjects and in IBS patients before and after receiving dietary guidance, respectively (P=0.007); the corresponding densities of peptide YY cells were 11.6±1.8, 10.8±1.7 and 16.8±2.1 cells/mm(2), respectively (P=0.06). The cell densities for both serotonin and peptide YY did not change significantly in the rectum. The densities of somatostatin cells in the rectum were 13.5±3.0, 13.2±3.0, and 22.3±3.2 cells/mm(2) for control subjects and for IBS patients before and after receiving dietary guidance, respectively (P=0.01). CONCLUSIONS: The densities of the large intestinal endocrine cells tend to normalize following dietary guidance that may have contributed to the improvement of the patients with IBS symptoms.

Effect of dietary management on the gastric endocrine cells in patients with irritable bowel syndrome.

BACKGROUND/OBJECTIVES: The gastric endocrine cells in patients with irritable bowel syndrome (IBS) tend to normalize following dietary guidance. The aim of the present study was to identify the gastric endocrine cell types that are changed following such dietary guidance. SUBJECTS/METHODS: Fourteen IBS patients and 14 healthy subjects were included in the study. Patients received three sessions of individual dietary management guidance. Gastroscopy was performed on both the controls and the patients at baseline and then again for the patients at 3-9 months after dietary guidance. Biopsy samples from the corpus and antrum were immunostained for all gastric endocrine cell types. Endocrine cells were quantified by computerized image analysis. RESULTS: The densities of the ghrelin cells for the controls and IBS patients before and after dietary guidance were 149.6 ± 36.2 (mean ± s.e.m.; 95% confidence interval (CI) 71.3-227.8), 114.5 ± 32.7 and 161.8 ± 37.8 cells/mm(2), respectively. The densities of the gastrin cells in these groups were 155.8 ± 21.0 (95% CI 110.3-201.2), 159.4 ± 24.3 and 211.6 ± 28.0 cells/mm(2), respectively; the corresponding densities of serotonin cells in the corpus were 18.2 ± 3.9 (95% CI 9.8-26.6), 10.6 ± 3.4 and 14 ± 2.0 cells/mm(2) and in the antrum were 44.6 ± 12.2 (95% CI 18.1-71.1), 1.7 ± 0.5 and 14.7 ± 6.3 cells/mm(2). The densities of the somatostatin cells in the corpus were 40.0 ± 7.7 (95% CI 23.5-56.5), 23.0 ± 3.0 and 37.3 ± 4.2 cells/mm(2), respectively, and in the antrum were 138.9 ± 22.0 (95% CI 91.4-186.3), 95.6 ± 15.9 and 86.0 ± 16.9 cells/mm(2), respectively. CONCLUSIONS: The densities of all of the gastric endocrine cell types changed towards the healthy control values in the IBS patients following a change in food intake.

Chromogranin A cell density in the rectum of patients with irritable bowel syndrome.

In a previous study, chromogranin A (CgA) cell density in the colon of patients with irritable bowel syndrome (IBS) was found to be reduced. It has been suggested that intestinal CgA cell density may be used as a marker for the diagnosis of IBS. The rectum harbours a larger number of large intestinal endocrine cells and is more accessible for biopsies than the colon. The present study aimed at determining the CgA cell density in the rectum of IBS patients. A total of 47 patients with IBS that fulfilled the Rome Criteria III (39 females and 8 males; average age, 38 years) were included. A total of 28 patients had diarrhea (IBS-D) and 19 had constipation (IBS-C) as the predominant symptom. A total of 27 subjects that underwent colonoscopy with rectal biopsies were used as the controls. These subjects underwent colonoscopy due to gastrointestinal bleeding (the source of which was identified as haemorrhoids or angiodysplasia; 19 females and 8 males; average age, 49 years), or health worries. The rectal biopsies were immunostained for CgA and quantified by computer image analysis. The CgA density in the controls was 206.3±22.2 (mean ± SEM), in all IBS patients 190.2±14.3, in IBS-D patients 188.8±14.7 and in IBS-C patients 195.3±34.1. There was no statistically significant difference between the controls, IBS, IBS-D or IBS-C patients (P=0.5, 0.5 and 0.7, respectively). The present study showed that although the rectum comprises the same endocrine cell types as the colon, attention must be paid when drawing conclusions regarding the whole large intestine from studies carried out on the rectum. This particularly applies when endocrine cells are investigated. As CgA cell density represents the total endocrine cell content of the rectum, changes in specific endocrine cells in IBS patients cannot be excluded.

The role of diet in the pathogenesis and management of irritable bowel syndrome (Review).

Most patients with irritable bowel syndrome (IBS) believe that diet plays a significant role in inducing IBS symptoms and desire to know what foods to avoid. It has been found that the intake of calories, carbohydrates, proteins and fat by IBS patients does not differ from that of the background population. IBS patients were found to avoid certain food items that are rich in fermentable oligo-, di- and monosacharides and polyols (FODMAPs), but they did have a high consumption of many other FODMAP-rich food items. The diet of IBS patients was found to consist of a low calcium, magnesium, phosphorus, vitamin B2 and vitamin A content. There is no consistent evidence that IBS patients suffer from food allergy, nor is there documented evidence that food intolerance plays a role in IBS symptoms. Abnormalities in gut hormones have been reported in IBS patients. As gut hormones control and regulate gastrointestinal motility and sensation, this may explain the abnormal gastrointestinal motility and visceral hypersensitivity reported in these patients. Guidance concerning food management which includes individually based restrictions of FODMAP-rich food items and individual evaluation of the effects of protein-, fat- and carbohydrate-rich/poor diets may reduce IBS symptoms.

Low densities of serotonin and peptide YY cells in the colon of patients with irritable bowel syndrome.

BACKGROUND: The gut hormones are important in regulating gastrointestinal motility. Disturbances in gastrointestinal motility have been reported in patients with irritable bowel syndrome (IBS). Reduced endocrine cell density, as revealed by chromogranin A, has been reported in the colon of IBS patients. AIMS: To investigate a possible abnormality in the colonic endocrine cells of IBS patients. METHODS: A total of 41 patients with IBS according to Rome Criteria III and 20 controls were included in the study. Biopsies from the right and left colon were obtained from both patients and controls during colonoscopy. The biopsies were immunostained for serotonin, peptide YY (PYY), pancreatic polypeptide (PP), entroglucagon, and somatostatin cells. Cell densities were quantified by computerized image analysis. RESULTS: Serotonin and PYY cell densities were reduced in the colon of IBS patients. PP, entroglucagon, and somatostatin-immunoreactive cells were too few to enable reliable quantification. CONCLUSION: The cause of these observations could be primary genetic defect(s), secondary to altered serotonin and/or PYY signaling systems and/or subclinical inflammation. Serotonin activates the submucosal sensory branch of the enteric nervous system and controls gastrointestinal motility and chloride secretion via interneurons and motor neurons. PYY stimulates absorption of water and electrolytes, and inhibits prostaglandin (PG) E2, and vasoactive intestinal peptide, which stimulates intestinal fluid secretion and is a major regulator of the "ileal brake". Although the cause and effect relationship of these findings is difficult to elucidate, the abnormalities reported here might contribute to the symptoms associated with IBS.

High chromogranin A cell density in the colon of patients with lymphocytic colitis.

Microscopic colitis (MC) is a chronic condition that is characterized by watery diarrhoea with normal appearance of the colonic mucosa. MC is subdivided into two distinctive entities: lymphocytic colitis (LC) and collagenous colitis (CC). The etiology and pathophysiology of LC remain to be determined. The present study included 9 female patients with LC, with an average age of 34 years. Subjects (n=25) who underwent colonoscopy were used as controls. The subjects underwent colonoscopy due to gastrointestinal bleeding, where the source of bleeding was identified as haemorrhoids, or due to health concerns. The control subjects included 18 females and 7 males, with an average age of 49 years. Colonoscopy was performed in both patient and control groups, and biopsies were obtained from different segments of the colon. The biopsies were immunostained with the avidin-biotin complex method for human leucocytes CD45, collagen type III and chromogranin A (CgA). CgA was quantified by computer image analysis. The density of CgA-immunoreactive cells in patients with LC was significantly higher than that in controls. The high density of colonic CgA, a common marker for endocrine cells, indicates the possibility that colonic hormones are involved in the pathophysiology of LC. Serotonin-containing cells are the major endocrine cell type in the colon and constitute approximately 88% of the total endocrine cell population. It is likely that the increase in colonic CgA in LC patients accounts for an increase in serotonin cells.

The prevalence of celiac disease in patients with irritable bowel syndrome.

The diagnosis of irritable bowel syndrome (IBS) is based on symptom assessment such as the Rome III criteria. It is sometimes difficult to clinically distinguish IBS from adult-onset celiac disease (CD). Individuals with CD presenting with relatively vague abdominal symptoms are at risk of been dismissed as having IBS. This study aimed to investigate the prevalence of patients with CD among those that fulfill the Rome III criteria for IBS from among patients referred to the gastroenterology section of our hospital over the last 5 years. The study included a total of 968 patients with an average age of 32 years (range 18-59 years). Females constituted 95% of all patients. Duodenal biopsies were obtained during standard gastroscopy. Sections from these biopsies were stained with haematoxylin and eosin and immunostained for human leucocytes CD45 using the avidin-biotin complex (ABC) method. The sections were then histopathologically examined. Four patients had CD: one with Marsh type 3b, and 3 with Marsh type 1. All four of these patients were positive for tissue transglutminase antibodies (anti-t-TG) IgA and were females aged 24, 20, 36 and 38 years. These 4 patients fulfilled the Rome III criteria for the sub-type IBS-diarrhea. This amounts to a prevalence of 0.4% of CD in IBS patients. The present findings support the notion that IBS patients should be routinely examined for CD. This applies to all subtypes of IBS.

Relative importance of abnormalities of CCK and 5-HT (serotonin) in Giardia-induced post-infectious irritable bowel syndrome and functional dyspepsia.

BACKGROUND: Post-infectious irritable bowel syndrome (PI-IBS) and functional dyspepsia (FD) have been described after both Campylobacter jejuni gastroenteritis and Giardia infection. After C. jejuni, there is increased rectal serotonin (5-HT)-containing EC cells and postprandial plasma 5-HT, while a pilot study suggested increased plasma cholecystokinin (CCK) after Giardia infection. AIM: To determine changes in plasma and duodenal mucosal 5-HT and CCK in Giardia-induced PI-IBS. METHODS: A total of 32 patients previously infected with Giardia and 19 who had recovered fully (controls) completed symptom questionnaires. Endoscopic duodenal biopsies were obtained from all subjects and immunohistochemically stained for CCK, 5-HT and CgA containing entero-endocrine cells and mast cells. 5-HT content was also assessed. Twenty-one of 32 patients and 19 controls consumed a high-carbohydrate meal, while fasting and postprandial plasma CCK and 5-HIAA were measured. RESULTS: Post-infectious irritable bowel syndrome patients had increased numbers of CCK cells (P = 0.02), but lower numbers of EC cells (P = 0.009). Plasma CCK did not differ significantly between the groups, but correlated significantly with postprandial dyspepsia scores (r = 0.5, P = 0.05). PI-IBS patients had significantly lower plasma 5-HIAA, before and after meal (P = 0.05) as well as more dyspepsia (P < 0.0001) compared with recovered subjects. CONCLUSIONS: Post-infectious bowel dysfunction following Giardia infection is associated with increased duodenal mucosal CCK. Postprandial dyspeptic symptoms correlate better with CCK than measures of 5-HT metabolism.

Ghrelin in patients with irritable bowel syndrome.

General gastrointestinal dysmotility occurs in patients with irritable bowel syndrome (IBS). Ghrelin seems to play an important role in regulating gastrointestinal motility. The present study was undertaken, therefore, to establish the possible role of ghrelin in the pathophysiology of IBS. Thirty-seven patients with IBS (19 had IBS-constipation and 18 IBS-diarrhoea) were included in this study. Ten healthy volunteers served as controls. After overnight fast, blood samples were drawn from patients and controls, and a gastroduodenal endoscopy was performed. Biopsies were taken from oxyntic mucosa and duodenum. Ghrelin cell density was determined by computer image analysis after immunohistochemical staining of the tissues. Total and active ghrelin were detected in tissue extracts and plasma by commercially available RIA and ELISA Kits. The density of ghrelin-immunoreactive cells in the oxyntic mucosa was significantly lower in IBS-constipation and significantly higher in IBS-diarrhoea patients than healthy controls (P<0.0001 and <0.0001, respectively). There was no statistical difference in total or active ghrelin between IBS patients and controls, regarding tissue extracts or plasma. In order to compensate for the increase and decrease in the ghrelin cell density, the synthesis and release of ghrelin may be decreased and increased in IBS-diarrhoea and IBS-constipation patients, respectively. It has been speculated that this compensatory mechanism may be subjected from time to time to fatigue with the subsequent increased and decreased synthesis and release of ghrelin in IBS-diarrhoea and IBS-constipation with a subsequent intermittent diarrhoea or constipation seen in these patients, respectively.

Ghrelin cell density in the gastrointestinal tracts of animal models of human diabetes.

Ghrelin cell density in the gastrointestinal tract of animal models of human diabetes type 1 and 2 was investigated. The animals used were non-obese diabetic (NOD) mice and obese diabetic mice. Ghrelin cells were detected by immunohistochemistry and quantified by computerized image analysis. Ghrelin-immunoreactive cells were detected in all animals studied. They were abundant in the oxyntic mucosa, patchy and few in the duodenum and rare in the colon. The density of ghrelin-immunoreactive cells decreased in diabetic, pre-diabetic NOD mice and in obese diabetic mice as compared to controls, though not statistically significant. It was concluded that the reduced density of ghrelin-immunoreactive cells in animal models of human diabetes type 1 and 2 might explain the slow gastric emptying and slow intestinal transit found in diabetes gastroenteropathy.

Comparison between triple therapy with octreotide, galanin and serotonin vs. irinotecan or oxaliplatin in combination with 5-fluorouracil/leukovorin in human colon cancer.

Human colon cancer cells were injected sub-cutaneously into 30 nude mice. After 8 days, the animals were divided into 3 equal groups. The first and second groups received an i.p. injection with 5-fluorouracil/leukovorin (5-FU/LV) for 5 days (20 mg and 10 mg/kg body weight respectively). On the first day of 5-FU/LV treatment, the first group received an i.p. injection of irinotecan (2.5 mg/kg body weight), and the second group received an i.p. injection with oxaliplatin (1 mg/kg body weight). The third group were injected i.p. with 100 microl saline solution containing octreotide, galanin and serotonin. Injections were given 3 times daily for 5 days with a total dose of 150 microg/kg body weight/day. Three days after the treatment, the animals were sacrificed. Whereas the animals treated with triple therapy held a stable body weight, animals treated with 5-FU/LV-irinotecan and 5-FU/LV-oxaliplatin had gradual weight loss, which amounted to approximately 25% of their body weight at the end of the experiment. Moreover, 2 mice in the group treated with 5-FU/LV-irinotecan died, most probably due to side effects. There was no statistically significant difference between the 3 groups regarding tumour proliferation, apoptosis, blood vessel density, EGF- and VEGF-expression. Treatment with triple therapy using octreotide, galanin and serotonin appear to be comparable to 5-FU/LV in combination with irinotecan and oxaliplatin. However, triple therapy seems to have a better safety profile.

Effects of triple treatment with octreotide, galanin and serotonin on a human pancreas cancer cell line in xenografts.

Human pancreas cancer cells were implanted s.c. in nude mice. After 11 days, the mice were divided into two groups of 13. The first group received sterile saline solution and the second received triple therapy containing octreotide, galanin and serotonin, 40 microg/kg/day as a continuous i.p. infusion via an implanted osmotic pump for 14 days. Triple therapy prolonged the survival rate of the mice bearing human pancreatic carcinoma. Both the volume and weight of tumours in mice given triple therapy were less than in controls (not statistically significant). The proliferation index and the labelling index for epidermal growth factor (EGF) increased significantly in mice given triple therapy vis-a-vis controls. There was no statistically significant difference between control and treated tumours as regards, apoptotic index, necrosis, or number of tumour blood vessels. The increased survival rate was attributed to the reduced tumour load, since both weight and volume were reduced. It is most probable that octreotide was the responsible agent. Further investigation with single and double combinations of octreotide, galanin and serotonin are needed to identify the cause of increased cell proliferation in tumours subjected to these bioactive substances. Identifying the agent(s) inducing pancreatic cancer cell proliferation may be useful in combining a new treatment, as antagonists to these bioactive substances are available.

Effects of single, double or triple combinations of octreotide, galanin and serotonin on a human pancreatic cancer cell line.

The human pancreatic cancer cell line (SW 1990) was exposed to 0.2 microg/ml of octreotide, galanin or serotonin as single, double or triple combinations. The tumor cells were checked at 3, 6 and 12 hours. In order to determine the number of viable cancer cells, the MTT-assay was used. Proliferation, apoptosis and the expression of epidermal growth factor were detected with immunohistochemistry using the avidin-biotin complex method. In addition, apoptosis was also detected with (TUNEL) method. The primary antibodies used were proliferating cell nuclear antigen (PCNA), anti-poly (ADP-ribose) polymerase (PARP) and anti-human epidermal growth factor. Single treatment with octreotide or serotonin reduced, the number of viable cells and the proliferation index at all observation times. Galanin increased the number of viable cells and the proliferation index. Whereas double treatments containing octreotide reduced the number of viable cells, those containing galanin increased the number. The effect of single, double or triple treatment on the apoptotic index obtained with both TUNEL method and PARP expression varied depending on the combination and the observation time. Octreotide did not affect the tumor cell expression of EGF. Galanin and serotonin, on the other hand, increased the expression of EGF. Whereas triple combination increased the expression of EGF after 6 h, all the other double combinations decreased this expression. It has been concluded that treatment with a combination of octreotide and serotonin may be useful in clinical settings.

Effects of triple therapy with octreotide, galanin and serotonin on a human colon cancer cell line implanted in mice: comparison between different routes of administration.

A human colon cancer cell line was implanted subcutaneously in nude mice. After 7 days, the animals were divided into four groups. The first group received an intraperitoneal (i.p.) continuous infusion by an osmotic pump, the second was given i.p. bolus injections, the third received continuous subcutaneous (s.c.) infusion by an osmotic pump and the fourth group was given bolus s.c. injections. Each group was divided into 2 subgroups. The first subgroup received triple treatment with octreotide, galanin, and serotonin, 40 microg/kg body weight/day of each. The second subgroup was given sterile saline solution. Treatment lasted for 14 days. The volume and wet weight of the tumours in all treated groups tended to decrease, but was statistically significant only in the group with continuous i.p. infusion. The number of viable cells tended to decrease in all the treated groups, but was not statistically significant. Proliferation index was significantly reduced in mice given triple therapy i.p. as bolus injection and as continuous infusion, as compared with their respective controls. The apoptotic index increased significantly in mice receiving triple therapy as continuous i.p. infusion as revealed by both the TUNEL method and by poly (ADP-ribose) polymerase (PARP) expression. The number of tumour blood vessels was significantly reduced in the mice given triple therapy as continuous i.p. infusion, as compared with controls. There was no statistical difference between animals treated by different routes, regarding proliferation or apoptosis of the cancer cells, or the number or mean luminal area of tumour blood vessels. The present investigation showed that regardless of the route of administration, triple therapy with octreotide, galanin and serotonin generally reduced the volumes, weights, viable cells, vascularization and proliferation of the tumours, as well as inducing apoptosis. Continuous i.p. infusion appears, however, to be the most effective route of administration.

Chronic idiopathic slow transit constipation: pathophysiology and management.

OBJECTIVE: Patients with idiopathic slow-transit constipation comprise a small proportion of the total population complaining of constipation. The purpose of this review is to present an update of pathophysiology of this disorder and its application in clinical management. METHODS: Medline was used to search English language articles published up to the end of September 2002 on the subject of slow-transit constipation. RESULTS AND CONCLUSIONS: Patients with idiopathic slow-transit constipation can be divided into 2 subgroups: 1. patients with normal proximal gastrointestinal motility and with onset of constipation in connection with childbirth or pelvic surgery. This subgroup may benefit from consideration of surgical treatment; 2. patients who have a dysfunctional enteric nervous/neuroendocrine system and exhibit colonic dysmotility as part of a generalised gastrointestinal dysmotility. Surgical approach in this subgroup seems to be unhelpful and medical treatment appears to be a better approach.

A comparison between double and triple therapies of octreotide, galanin and serotonin on a rat colon carcinoma.

Sixty female nude mice (C578L/6jBom-nu) were injected with 100 microl cell suspension containing 2 x 10(6) viable cells of an N-methyl-N-nitroguanidine-induced rat colonic adenocarcinoma. After seven days the animals were divided into five groups. The first group received only saline and served as a control group. The second group received a triple therapy of octreotide, galanin and serotonin (20 microg/kg). The last three groups received double therapies of octreotide/galanin, octreotide/serotonin or galanin/serotonin (20 microg/kg). They were treated twice a day for five days. Tumour volume and weight, relative volume density of tumour-feeding blood vessels and of tumour necrotic tissue, as well as apoptotic and proliferation indices were determined. Animal weight, food consumption, faeces weight and its water content were recorded before and after treatment. Tumour volume was significantly reduced only in the group that received the triple therapy. The volume density of the tumour-feeding blood vessels was significantly reduced in the treated groups with the exception of the group that received octreotide and serotonin. Increased relative volume density of tumour necrotic tissue occurred only in the group treated with triple therapy. Apoptotic indices were significantly increased in all treated groups. No statistical difference was found between treated animals and controls regarding proliferation indices, food consumption, faeces weight and water content or animal weight. In conclusion, double therapy using two of the gastrointestinal bioactive substances, octreotide, galanin and serotonin, has certain effects on colon cancer cells. To cause a considerable tumour necrosis, triple therapy seems to be required. Both double and triple therapy seem to lack obvious side-effects.

The possible role of the gut neuroendocrine system in diabetes gastroenteropathy.

Gastrointestinal symptoms such as nausea and vomiting, heartburn, abdominal pain, diarrhoea, constipation and faecal incontinence are common in patients with diabetes. Diabetes gastroenteropathy is a clinically relevant problem. In addition to the increased morbidity it causes, it results in severely impaired metabolic control, which in turn increases the risk of hyper-/hypoglycaemia. Moreover, the poorly controlled blood glucose level increases the risk of secondary diabetes complications, namely, retinopathy, nephropathy, neuropathy and cardiovascular affection. Gastrointestinal symptoms may also cause malnutrition in patients with diabetes, which, together with the disturbed immune defence in diabetes, may cause intercurrent infections. Gastrointestinal symptoms in patients with diabetes are attributed to disturbed gastrointestinal motility. Gastrointestinal dysmotility in diabetes is believed to be caused by autonomic neuropathy and/or hyperglycaemia. The neuroendocrine system of the gut secretes peptides/amines that play an important role in regulating gastrointestinal motility. It is conceivable, therefore, to assume that a disturbance in this regulatory system may contribute to the pathogenesis of gastrointestinal complications in diabetes. The present review gives an updated overview of the abnormalities in the gastrointestinal neuroendocrine system in diabetes, speculates upon the possible role of these abnormalities in the pathogenesis of diabetes gastroenteropathy and, finally, predicts the possible clinical implications of these findings.

Reduction of free radical activity in amyloid deposits following liver transplantation for familial amyloidotic polyneuropathy.

OBJECTIVES: Liver transplantation halt the progress of familial amyloidotic polyneuropathy (FAP). Oxidative stress has been implicated in amyloid toxicity and formation. The objective of this study was to establish whether markers for oxidant stress and antioxidant capacity change following liver transplantation in patients with FAP. DESIGN: Morphometric and biochemical study. SETTING: Tertiary referral centre. SUBJECTS: Duodenal biopsy samples from 16 patients, taken before and after liver transplantation were used for morphometry. Serum samples from 14 patients, seven of whom had received transplants, were analysed regarding antioxidant capacity. INTERVENTION: Liver transplantation. MAIN OUTCOME MEASURES: Immunohistochemistry was used to stain for the lipid peroxidation product 4-hydroxynonenal (HNE), and Congo red staining was used for amyloid detection. Positive areas were quantified by point counting. Total antioxidant capacity (TAC) was measured with a colourimetric assay. RESULTS: In tissue, a decrease of HNE was noted after liver transplantation, whereas no significant changes were detected for amyloid deposits. No difference between transplanted and not transplanted patients was noted for total antioxidant capacity measured in serum. CONCLUSION: To our knowledge, this is the first description of a reduction of markers for free radical activity after cessation of amyloid formation. The findings implicate that amyloid formation in transthyretin (TTR) amyloidosis generates oxidative stress, whereas amyloid deposits as such are less toxic to sourrounding tissues.

Abnormal gastrointestinal endocrine cells in patients with diabetes type 1: relationship to gastric emptying and myoelectrical activity.

BACKGROUND: Gastrointestinal symptoms in patients with diabetes are believed to be caused by gastrointestinal dysmotility and secretion/absorption disturbances, and the gut endocrine cells play an important part in regulating these two functions. Studies on animal models of human diabetes type I revealed abnormality in these cells, but it is unknown whether abnormality also occurs in patients with diabetes. METHODS: Eleven patients with long duration of diabetes type I and organ complications, as well as gastrointestinal symptoms, were studied. Endocrine cells in different segments of the gastrointestinal tract were detected by immunocytochemistry and quantified by computerized image analysis. Gastric emptying was measured by scintigraphy and gastric myoelectric activity was determined by electrogastrography. RESULTS: An abnormal density of gastrointestinal endocrine cells was found in patients with diabetes. This abnormality occurred in all segments of the upper and lower gastrointestinal tract investigated, and included most of the endocrine cell types. The patients showed delayed gastric emptying, which correlated closely with the acute glucose level, but did not correlate with HbA1c. Gastric emptying also correlated closely with the density of duodenal serotonin and secretin cells. The patients exhibited bradygastrias and tachygastrias. These dysrhythmias, however, did not differ significantly from controls. CONCLUSIONS: The endocrine cells are the anatomical units responsible for the production of gut hormones, and the change in their density would reflect a change in the capacity of producing these hormones. The abnormality in density of the gastrointestinal endocrine cells may contribute to the development of gastrointestinal dysmotility and the symptoms encountered in patients with diabetes.

Comparison of amyloid deposits and infiltration of enteric nervous system in the upper with those in the lower gastrointestinal tract in patients with familial amyloidotic polyneuropathy.

Gastrointestinal (GI) complications in familial amyloidotic polyneuropathy (FAP) are invariably present during the course of the disease. The aim of this study was to investigate amyloid deposits in the myenteric plexus of the stomach and small intestine in FAP patients and compare the results with those of the colon. Six FAP patients were included in the study. The myenteric plexus and the number of macrophages (CD68) and blood vessels were immunostained and quantified by computerised image analysis. Double staining for amyloid and nerve elements was used to detect amyloid infiltration in the myenteric plexus. Amyloid was found predominantly in the walls of blood vessels, and was detected in the nerves of five FAP patients and in 18% of the examined ganglia of the myenteric plexus of the stomach. In the small intestine, 6% of examined ganglia showed amyloid deposits. In contrast, no deposits were found in the myenteric plexus of the colon. CD68-positive cells showed no difference in three parts of the GI tract. Most amyloid deposits were noted in the stomach, followed by the small intestine. There are significantly more blood vessels in the stomach and small intestine compared with the colon, and the amount of amyloid correlated with the number of blood vessels, and not with the amount of nerves and ganglia. The enteric nerve system is not a targeted organ for amyloid deposition in FAP.