Hidetaka Matsui

Molecular characterization and distribution of motilin family receptors in the human gastrointestinal tract.

BackgroundMotilin and ghrelin have been recognized as important endogenous regulators of gastrointestinal motor function in mammals, mediated respectively by the motilin receptor and by the closely related ghrelin receptor. The aims of this study were to explore the distribution of motilin and ghrelin receptors along the human gastrointestinal tract and to establish the molecular nature of the human motilin receptor.MethodsPost mortem and surgical human tissue specimens with no hemorrhage, necrosis, or tumor were obtained from various parts of the gastrointestinal tract. We analyzed levels of expression of mRNA for motilin and ghrelin receptors and examined their molecular identities. Portions of some specimens were also studied by immunohistochemistry for expression of the motilin and ghrelin receptor.ResultsThe long form of the motilin receptor, but not the short form, was expressed in all parts of the gastrointestinal tract, and expressed at higher levels in muscle than in mucosa. Motilin receptor immunoreactivity was present in muscle cells and the myenteric plexus, but not in mucosal or submucosal cells. In contrast, ghrelin receptor mRNA was expressed equally in all parts of the gastrointestinal tract, with similar levels of expression in mucosal and muscle layers.ConclusionsBoth the motilin and ghrelin receptors are expressed along the human gastrointestinal tract, but they have clearly distinct distributions in regard to both level and layer. The diffuse muscle expression of the motilin receptor, at both the levels of the gene and the protein product, along the entire gastrointestinal tract makes it a useful potential target for motilide drugs for dysmotility.

Macrophage migration inhibitory factor in the sera and at the colonic mucosa in patients with ulcerative colitis: clinical implications and pathogenic significance.

Background Inflammatory cytokines produced by activated macrophages are implicated in the pathogenesis of ulcerative colitis (UC). With the theory that macrophage migration inhibitory factor (MIF) may have a role in the accumulation of macrophages, we studied MIF in UC.

Macrophage migration inhibitory factor activates antigen‐presenting dendritic cells and induces inflammatory cytokines in ulcerative colitis

The level of macrophage migration inhibitory factor (MIF) and the functions of dendritic cells (DC) are up‐regulated in the peripheral blood, and the numbers of MIF‐expressing cells and mature DC are increased at the colonic mucosa from patients with ulcerative colitis (UC). However, a functional relationship between MIF and DC, and the role of MIF in the pathogenesis of UC, are not clear. In this study, we showed that a pure population of peripheral blood DC is a new and still unknown source of MIF. DC from UC patients produced significantly higher levels of MIF (17·5 ± 9·8 ng/ml, n = 10) compared with patients with Crohn’s disease (CD) (4·6 ± 2·5 ng/ml, n = 5, P < 0·01) and control subjects (5·0 ± 2·6 ng/ml, n = 10, P < 0·01). A double immunofluorescence study revealed the expression of MIF by CD83‐positive mature DC at the colonic mucosa from UC patients. Blood DC treated with high amounts of MIF (500 ng/ml) showed a significantly higher stimulatory capacity (43287 ± 5998 CPM, n = 5) in an allogenic mixed leucocyte reaction compared with untreated DC (27528 ± 8823 CPM, n = 5, P < 0·05). Study of intracellular cytokine expression showed that MIF induced significant levels of interleukin (IL)‐1β and IL‐8 in monocytes and DC from UC and CD patients. These results showing the capacity of MIF to induce increased functional capacity of DC, and to produce IL‐1β and IL‐8 from monocytes and DC, indicate a role of MIF in the induction and/or perpetuation of the inflammatory environment in UC.

Decreased interferon‐α production and impaired T helper 1 polarization by dendritic cells from patients with chronic hepatitis C

Patients with chronic hepatitis C (CHC) are unable to prime and maintain vigorous T cell responses that are initiated during the acute phase of hepatitis C virus (HCV) infection. As dendritic cells (DCs) induce and regulate both innate and adaptive immune responses, the aim of this study was to analyse two critical functions of DCs: firstly, production of interferon (IFN)‐α and, secondly, polarization of T helper 1 lymphocytes. The frequencies of plasmacytoid DC (PDC) and myeloid DC (MDC) were estimated in 63 patients with CHC and 34 normal controls using four‐colour flow cytometry. Circulating DCs were isolated from peripheral blood of CHC patients (n = 10) and normal controls (n = 10). These DCs were cultured with herpes simplex virus‐1 to evaluate their capacity to produce IFN‐α. The capacity of DCs to induce polarization of autologous naive CD4+ T lymphocytes to IFN‐γ‐producing effector T lymphocytes was also assessed. The frequencies of PDCs producing intracellular IFN‐α (P < 0·01) and the levels of IFN‐α in culture supernatant of PDCs (P < 0·01) were significantly lower in patients with CHC compared to those of normal controls. The numbers of MDC were significantly lower in patients with CHC (8·2 (6·0)/µl, median (interquartile range), n = 63) compared to normal control (11·7 (7·8)/µl, n = 34) (P < 0·01). Moreover, DCs from patients with CHC induced significantly lower numbers of IFN‐γ‐producing effector T lymphocytes compared to that of controls (P < 0·01). This study indicates that the low IFN‐α‐producing capacity and impaired T helper 1 polarization ability of DCs from patients with CHC might be responsible for the typical low anti‐HCV immune responses in these patients.

Characterization of antigen-presenting dendritic cells in the peripheral blood and colonic mucosa of patients with ulcerative colitis.

Objective Increased lymphocyte activation and production of inflammatory cytokines are implicated in the pathogenesis of ulcerative colitis. Because antigen-presenting dendritic cells play a cardinal role in the activation and survival of activated lymphocytes, the aim of the present study was to characterize dendritic cells in ulcerative colitis. Design This study was designed to compare the phenotypes and functions of peripheral blood dendritic cells among healthy normal volunteers and patients with ulcerative colitis or Crohns disease. Activated dendritic cells were also localized at the colonic mucosa. Methods Peripheral blood dendritic cells were generated from 15 patients with ulcerative colitis, 10 patients with Crohns disease and 15 healthy control volunteers. The stimulatory capacities of dendritic cells were analysed in an allogenic mixed lymphocyte reaction. Nitric oxide was detected by the Griess method. Single- and dual-colour flow cytometry was employed to study the levels of maturation of dendritic cells. Activated dendritic cells were localized immunohistochemically in the colonic mucosa. Results In comparison to normal controls, peripheral blood dendritic cells from patients with ulcerative colitis showed significantly increased stimulatory capacities (P < 0.05) and produced significantly higher levels of nitric oxide (P < 0.05). The numbers of activated dendritic cells were also significantly higher in ulcerative colitis (P < 0.05). Mature and activated dendritic cells expressing the CD83 antigen were detected at the inflamed colonic mucosa in patients with ulcerative colitis and Crohns disease. Conclusions Activated and mature dendritic cells may have a role in the induction of an exacerbated immune response in ulcerative colitis. This study provides the scientific and logical basis for blocking the maturation and activation of dendritic cells in ulcerative colitis as a new therapeutic intervention.

Clinical characteristics of autoimmune hepatitis with histological features of acute hepatitis

The number of patients with autoimmune hepatitis with histological features of acute hepatitis (AIH-AH) has been increasing recently. Here, the clinical features of patients with AIH-AH have been compared with those of patients with AIH with histological findings of chronic hepatitis (AIH-CH) and liver cirrhosis (AIH-LC). The levels of total serum bilirubin (P<0.05) and serum transaminases (P<0.05) were significantly higher in patients with AIH-AH than in patients with AIH-CH and AIH-LC. However, the serum levels of gamma-globulin (P<0.05) and immunoglobulin G (P<0.05) were significantly lower in AIH-AH than in patients with AIH-CH and AIH-LC. The aggregate score according to the criteria of the International Autoimmune Hepatitis Group in 1999 was also significantly lower in AIH-AH patients than in patients with AIH-CH and AIH-LC (P<0.05). Eleven patients with AIH-AH were treated with corticosteroids, however, the clinical response was insignificant in three patients. In summary, it is difficult to diagnose of patients with AIH-AH using the criteria of the International AIH scoring system. We wish that this scoring system would be modified in the near future.

Recent clinical features of Wilson’s disease with hepatic presentation

BackgroundWe carried out this study to evaluate recent clinical features of Wilson’s disease (WD) with hepatic presentation, especially in terms of age, degree of liver injury, and association with hepatocellular carcinoma (HCC).MethodsSixteen patients with hepatic manifestations were diagnosed with WD in the period 1976–2003. We divided this period into two periods, “past” and “recent”. The diagnosis was based on the presence of Kayser-Fleisher rings, low serum copper levels, low serum ceruloplasmin levels, increased urinary copper concentrations before or after D-penicillamine challenge, and increased hepatic copper concentrations. This retrospective study was done at Ehime University Hospital.ResultsFour patients, including a pair of siblings, had a family history of WD. Four patients had parental consanguinity. There were 6 patients aged over 40 years in the recent period, whereas no patients in the past period were over 40. Four patients had neurological manifestations. Ten patients had liver cirrhosis and 5 had chronic hepatitis. Two had fatty liver without obesity. All patients in the past period had liver cirrhosis. Three patients with liver cirrhosis were found to have HCC during the follow up. All patients were treated with either D-penicillamine or trientine chloride, or both. However, four patients had to discontinue these agents due to the side effects.ConclusionsRecently, the number of patients diagnosed with WD has been increasing, not only in terms of those with classical-type WD but also in terms of elderly patients or patients with non-cirrhotic liver injury such as fatty liver and chronic hepatitis. The various clinical features of WD should be recognized and particular attention should focus on HCC as a complication.

Characteristic endoscopic features of portal hypertensive enteropathy

BackgroundDouble-balloon endoscopy (DBE) and capsule endoscopy have opened up a new field of investigation regarding the small intestine. Although DBE has been widely used for diagnosis and treatment of different lesions in the small intestine, there is a paucity of information regarding endoscopic features of the small intestine in patients with liver cirrhosis (LC).MethodsEndoscopic images of the small intestine were taken in 21 patients with LC by DBE (EN-450P5/20 or EN-450T5/W). Biopsy specimens were taken from various parts of the small intestine and examined microscopically. Different endoscopic features of the small intestine were compared in relation to the clinical parameters of these patients.ResultsErythema and telangiectasia were observed in five patients (24%) and one patient (5%), respectively. In eight patients (38%), the small intestinal mucosa was edematous, and the intestinal villi of these patients were swollen and rounded, resembling herring roe. The patients with a herring roe appearance in the small intestine had advanced LC (Child’s classification B and C), and all of them also had portal hypertensive gastropathy and portal hypertensive colopathy. In comparison with patients without a herring roe appearance in the small intestine, patients with a herring roe appearance had a significantly increased spleen volume (P < 0.05) and decreased platelet counts (P < 0.05).ConclusionsAlthough preliminary, this study indicated that DBE may be useful for detecting different types of endoscopic lesions in patients with LC. A herring roe appearance seems to be one of the characteristic features of portal hypertensive enteropathy. However, further study will be required to develop insights about its pathogenesis.

Esophagogastric varices as a prognostic factor for the determination of clinical stage in patients with primary biliary cirrhosis

BackgroundPrimary biliary cirrhosis (PBC) is usually classified as either asymptomatic PBC (a-PBC) or symptomatic PBC (s-PBC). Although the proportion of a-PBC versus s-PBC patients has been consistently increasing, it is not clear whether the present criteria for the staging of PBC are optimal or not. We investigated the clinical stage of PBC patients from the standpoint of esophagogastric varices (EGV).MethodsOne hundred and nine PBC patients were enrolled in this retrospective study. We investigated the clinical features of PBC based on laboratory data, histological stage, symptoms, and existence of EGV. In addition, the clinical course and prognosis in patients who were periodically followed up were also studied.Results(1) EGV was detected in a-PBC patients, and there was no difference in the grade of EGV between a-PBC and s-PBC patients. (2) a-PBC patients with EGV had more liver damage than those without EGV, and a-PBC patients with EGV had a poorer prognosis than those without EGV. (3) Three of 11 patients who progressed from a-PBC to s-PBC within 3 years had EGV. (4) One of 3 a-PBC patients with EGV had progressed to s-PBC at 3-year follow-up.ConclusionsThese results indicate that EGV is one of the most important factors for evaluating PBC. Therefore, we would like to propose that a-PBC patients with EGV should either be included in the presently defined s-PBC class, or that new prognostic classes of PBC be created that include EGV as a prognostic factor.

Clinical features of symptomatic primary biliary cirrhosis initially complicated with esophageal varices

BackgroundEsophageal varices (EV), one feature of portal hypertension, have been regarded as a late complication of liver diseases. However, accumulating evidence indicates that EV sometimes develop early during the course of primary biliary cirrhosis (PBC). The prognosis is usually poorer for patients with symptomatic PBC than for those with asymptomatic PBC. Nevertheless, the clinical features and prognosis of patients with PBC whose initial symptoms are EV have not been clarified.MethodsThe clinical features and the prognosis of patients who initially developed EV without other symptoms (v-PBC) were retrospectively investigated in 54 patients with symptomatic PBC.ResultsThe leukocyte and platelet counts were lower in patients with v-PBC than in those with PBC accompanied by other symptoms (s-PBC). Liver function tests, autoantibodies, and histological stage did not differ between patients with v-PBC and those with s-PBC. Although the prognosis did not differ, the incidence of hepatocellular carcinoma was significantly higher in v-PBC than in s-PBC (P = 0.0037).ConclusionsThese data indicate that v-PBC is a hypercarcinogenic state and constitutes a new subgroup of PBC.