Shinichi Kasai

Colonic Vascular Conductance Increased by Daikenchuto via Calcitonin Gene-Related Peptide and Receptor-Activity Modifying Protein 1

BACKGROUND Daikencyuto (DKT) is a traditional Japanese medicine (Kampo) and is a mixture of extract powders from dried Japanese pepper, processed ginger, ginseng radix, and maltose powder and has been used as the treatment of paralytic ileus. DKT may increase gastrointestinal motility by an up-regulation of the calcitonin gene-related peptide (CGRP). CGRP is also the most powerful vasoactive substance. In the present study, we investigated whether DKT has any effect on the colonic blood flow in rats. MATERIALS AND METHODS Experiments were performed on fasted anesthetized and artificially ventilated Wistar rats. Systemic mean arterial blood pressure and heart rate were recorded. Red blood cell flux in colonic blood flow was measured using noncontact laser tissue blood flowmetry, and colonic vascular conductance (CVC) was calculated as the ratio of flux to mean arterial blood pressure. We examined four key physiological mechanisms underlying the response using blocker drugs: CGRP1 receptor blocker (CGRP(8-37)), nitric oxide synthase inhibitor, vasoactive intestinal polypeptide (VIP) receptor blocker ([4-Cl-DPhe6, Leu17]-VIP), and substance P receptor blocker (spantide). Reverse transcription-polymerase chain reaction was used for the detection of mRNA of calcitonin receptor-like receptor, receptor-activity modifying protein 1, the component of CGRP 1 receptor and CGRP. After laparotomy, a cannula was inserted into the proximal colon to administer the DKT and to measure CVC at the distal colon. RESULTS Intracolonal administration of DKT (10, 100, and 300 mg/kg) increased CVC (basal CVC, 0.10 mL/mmHg) from the first 15-min observation period (0.14, 0.17, and 0.17 mL/mmHg, respectively) and with peak response at either 45 min (0.17 mL/mmHg by 10 mg/kg), or 75 and 60 min (0.23 and 0.21 mL/mmHg by 100 and 300 mg/kg, respectively). CGRP(8-37) completely abolished the DKT-induced hyperemia, whereas nitric oxide synthase inhibitor partially attenuated the DKT-induced hyperemia. [4-Cl-DPhe6, Leu17]-VIP and spantide did not affect the hyperemia. Japanese pepper significantly increased CVC at 45 min or later, whereas ginseng radix only showed a significant increase at 15 min. Reverse transcription-polymerase chain reaction showed that mRNA for calcitonin receptor-like receptor, receptor-activity modifying protein 1, and CGRP were expressed in rat colon and up-regulated by DKT. CONCLUSIONS The present study demonstrated that DKT increased CVC, which was mainly mediated by CGRP and its receptor components.

Activated hepatic stellate cells overexpress p75NTR after partial hepatectomy and undergo apoptosis on nerve growth factor stimulation.

Abstract: Background: Expression of neurotrophins (NTs) and their receptors is increased during hepatic regeneration, but their role is not well understood.

Effect of Ecabet Sodium Enema on mildly to moderately active ulcerative proctosigmoiditis: an open-label study

OBJECTIVES:Ecabet sodium (ES), a nonabsorbable antigastric ulcer agent, has been shown to adhere to the region of an ulcer. It topically enhances gastric mucosal defensive factors such as the endogenous prostaglandins, capsaicin-sensitive sensory nerves, nitric oxide, and mucin. All of these mucosal defensive factors play an important role in maintaining the mucosal integrity of the colon and rectum. Therefore, we investigated the effect of ES in patients with mildly to moderately active ulcerative proctosigmoiditis.METHODS:In an open-label study, seven patients with mildly to moderately active ulcerative colitis (UC) who had an inflamed mucosa in the rectum and/or sigmoid and were resistant to 4-wk topical and systemic standard treatment were treated with an ES enema b.i.d. for 14 days. The enema consisted of ES (1 g) and tepid water (20 or 50 ml). These patients were assessed by the Clinical Activity Index, colonoscopically, and histologically before and after the ES therapy. The ES therapy was started after obtaining informed consent from the patients.RESULTS:Six of the seven patients responded to therapy and achieved clinical, endoscopic, and histological remissions. One patient was withdrawn because of increased stool frequency. All six patients who completed the study showed a significant change in the mean Clinical Activity Index score from 5.3 ± 1.4 (mean ± SD) to 0.5 ± 0.8 (p < 0.05), in the colonoscopic score from 3.0 ± 0.9 to 0.8 ± 0.4 (p < 0.05), and in the histological score from 2.7 ± 0.5 to 0.5 ± 0.6 (p < 0.05), and achieved remission at the end of the study. There were no side effects attributable to the ES therapy. Five of the six patients are still in clinical remission after a median follow-up period of 5 months.CONCLUSIONS:The ES enemas proved to be a safe and potentially useful adjuvant therapy currently available for treating patients with mildly to moderately active ulcerative proctosigmoiditis. A controlled study is necessary to confirm our results.

The beneficial effect of dibutyryl cyclic adenosine monophosphate on warm ischemic injury of the rat liver induced by cardiac arrest.

Dibutyryl cAMP (DBcAMP) has a high membrane permeability, and maintenance of the intracellular cAMP concentration may improve the viability of organs. In this study, the effect of DBcAMP pretreatment on warm ischemic injury of rat livers was evaluated. Warm ischemic liver injury was induced in adult Wistar rats weighing 250-280 g by leaving them at room temperature (22-25 degrees C) after cardiac arrest. The hepatic cAMP concentration, %ATP, and trypan blue-positive nuclear ratio were determined after different durations of warm ischemia. In addition, transaminase and endothelin-1 (ET-1) release into the perfusate were examined during 60 min of isolated liver perfusion with Krebs-Henseleit solution. The optimal dose and time of DBcAMP pretreatment were determined to be 15 mg/kg and 60 min prior to warm ischemia, respectively. Data on the trypan blue-positive nuclear ratio and the release of transaminases and ET-1 revealed that warm ischemia first damaged the endothelial cells and then the hepatocytes. DBcAMP pretreatment appeared to protect the liver from warm ischemic injury by increasing the intracellular cAMP concentration and stabilizing the cell membranes of endothelial cells and hepatocytes.

Encapsulated hepatocyte transplantation for the treatment of D-galactosamine-induced acute hepatic failure in rats

Intraperitoneal transplantation of hepatocytes encapsulated with calcium alginate gel produced a marked improvement in the survival rate (75%) of rats with D-galactosamine (D-gal)-induced acute hepatic failure (AHF) when compared to the rate of 50% in rats undergoing free hepatocyte transplantation (HCTX). The viability of encapsulated hepatocytes was still 70% at 36 h after transplantation, and a gradual improvement in the serum glutamic oxaloacetic transaminase (GOT) and total bilirubin values was observed after encapsulated HCTX. Moreover, the arterial blood ketone body ratio (AKBR) remained within the normal range for the whole period of the investigation (60 h after transplantation), and histological investigation of the liver at 36 h demonstrated only slight inflammatory cell infiltrates without hepatocellular necrosis. The phagocytic index rose immediately after encapsulated HCTX and remained high subsequently. A prostaglandin inhibitor, indomethacin, blocked the improvement in survival rate, serum GOT, and AKBR of rats with D-gal-induced AHF despite encapsulated HCTX. Furthermore, no increase in the phagocytic index was observed. Indomethacin apparently suppressed the activation of Kupffer cells by encapsulated HCTX, which then failed to improve the survival of rats with D-gal-induced acute hepatic failure. Our results indicate that the reticuloendothelial system seems to play an important role in the efficacy of encapsulated HCTX in rats with D-gal-induced AHF.

Expression of NGF in hepatocellular carcinoma cells with its receptors in non-tumor cell components

Nerve growth factor (NGF) is suggested to have a role in tumor progression in addition to its role in differentiation and survival of neuronal cells. We investigated expression of NGF and its receptors, TrkA and p75NTR, in hepatocellular carcinomas (HCCs). Although hepatocytes and hepatic stellate cells (HSCs) showed respectively weak and intense NGF immunostaining in the background livers of patients suffering from liver cirrhosis (LC) or chronic hepatitis (CH), intense staining was demonstrated in HCC cells of 33 of 54 (61.1%) tumors. RT‐PCR detected NGF mRNA in 7 freshly‐isolated HCC samples, and in 2 of 4 cases, in which both background livers and tumors could be analyzed, NGF mRNA was more abundant in the tumors than the background livers. TrkA was detected in the smooth muscle cells of hepatic arteries, but it was negative in tumor cells as well as non‐neoplastic hepatocytes. p75NTR and α‐smooth muscle actin (αSMA) was expressed in HSCs in the background liver and fibroblast‐like cells in stromal septa, whereas HSCs within the HCC tissues were mostly negative for p75NTR but positive for αSMA. This suggests that HSCs in HCC have a different property from those in background livers. Furthermore, the stromal septa contained abundant nerve fibers, which may be related to the increased NGF expression in HCC cells. NGF and its receptors are then thought to have a role in cellular interactions involving HCC cells, HSCs, arterial cells and nerve cells in HCC tissues.

Histopathological assessment of multidrug resistance in gastric cancer: expression of P-glycoprotein, multidrug resistance-associated protein, and lung-resistance protein.

Because local recurrence is common after a curative resection for advanced gastric cancer, there has been significant interest in adjuvant chemotherapy. However, the overall effect of chemotherapy remains debatable regarding patients with advanced gastric adenocarcinoma. Multidrug resistance is thought to be a major cause of failure in cancer chemotherapy, and thus the expression of P-glycoprotein (P-Gp), multidrug resistance-associated protein (MRP), and lung-resistance protein (LRP) in tumor cells was evaluated by immunohistochemistry. In 20 gastric adenocarcinomas, 11 (55%), 2 (10%), and 0 (0%) were positive for MRP, LRP, and P-Gp. In malignant lymphomas, only 3 out of 10 cases were positive for MRP (30%). The positive rate of MRP staining was significantly higher in well and moderately differentiated adenocarcinomas (80%) than in poorly differentiated adenocarcinomas (20%). With regard to the degree of MRP expression and histological cell type, higher grades (grade 2–3) were observed only in well and moderately differentiated adenocarcinomas. In terms of the positive-stained cells and staining intensity, heterogeneity was observed in the staining profile of MRP. The proliferative cell nuclear antigen labeling index (PCNA LI) of MRP-positive and MRP-negative cases was 49.3%±11.6% and 49.4±6.9%, respectively. No correlation was observed between the MRP expression and PCNA LI. In conclusion, the incidence of MRP expression in gastric cancer was the highest in three different multidrug resistance-related epitopes. An evaluation of the MRP expression thus seemed to be beneficial for determining the optimal strategy of chemotherapy.

Angiolipoma of the Colon with Right Lower Quadrant Abdominal Pain

Background/Aim: An angiolipoma is a common benign neoplasm with a characteristic vascular component that occurs in the subcutaneous tissue and rarely in the gastrointestinal tract. We report on a 69-year-old man with a submucosal angiolipoma in the cecum. Methods: This patient was treated with a laparoscopy-assisted ileocecostomy, and a side-to-side anastomosis was performed extracorporeally. Results: A light microscopic study supported the diagnosis of an angiolipoma of the colon. After 5 years of follow-up, the patient has no symptoms or signs of recurrence. Conclusion: The colonic angiolipoma was successfully removed using a minimally invasive laparoscopic technique.

Metastatic seeding of bile duct carcinoma in the transhepatic catheter tract: Report of a case

We describe herein the case of a 51-year-old woman in whom metastatic tumor seeding of the percutaneous transhepatic biliary drainage tract occurred following a pancreatoduodenectomy for carcinoma of the distal common bile, duct. An abdominal computed tomography scan done 6 months after the initial operation detected a hepatic lesion located at the site of the previous percutaneous transhepatic biliary drainage tract. Implantation of bile duct carcinoma in the drainage tract was diagnosed, and the recurrent tumor was successfully resected by performing a subsegmentectomy of segment 3 and removal of the adjacent abdominal wall. At present, 5 years and 4 months after the second resection, the patient is in good health without any signs of recurrence. This case report demonstrates that an aggressive surgical approach should be performed for tumor seeding of a transhepatic biliary catheter tract.

Effects of Bone Marrow and Hepatocyte Transplantation on Liver Injury

BACKGROUND The therapeutic effects of bone marrow and hepatocyte transplantation were investigated regarding the treatment of retrorsine-partial hepatectomy-induced liver injury. METHODS Analbuminemic F344alb rats were given two doses of retrorsine 2 wk apart, followed 4 wk later by transplantation with F344 rat bone marrow cells or hepatocytes immediately after a two-thirds hepatectomy. The survival rate, liver regeneration rate, liver functions, albumin-positive hepatocytes, and normal albumin gene sequences in the liver and serum albumin levels were investigated in the recipients. RESULTS Although 65% retrorsine/partial hepatectomy-treated F344alb died between 1 and 11 d after the partial hepatectomy, only 27.5% of the animals died following bone marrow transplantation, and 50% with hepatocyte transplantation. Both bone marrow and hepatocyte transplantation ameliorated acute liver injury after a partial hepatectomy. Bone marrow transplantation yielded a very small increase in the number of albumin-positive hepatocytes in the liver, while hepatocyte transplantation resulted in massive replacement of the liver tissues by the donor hepatocytes associated with an elevation of serum albumin after an extended time. CONCLUSIONS Both bone marrow and hepatocyte transplantation could prevent acute hepatic injury, conceivably due to a paracrine mechanism.