Efficacy of prophylactic clip closure in reducing the risk of delayed bleeding after colorectal endoscopic submucosal dissection in patients on anticoagulant therapy: Multicenter prospective study.

OBJECTIVES: The high rate of delayed bleeding after colorectal endoscopic submucosal dissection (ESD) in patients undergoing anticoagulant therapy remains a problem. Whether prophylactic clip closure reduces the rate of delayed bleeding in these patients is unclear. This study aimed to evaluate the efficacy of prophylactic clip closure in patients receiving anticoagulants. METHODS: This multicenter prospective interventional trial was conducted at nine referral centers in Japan. Patients regularly taking anticoagulants, including warfarin potassium or direct oral anticoagulants, and undergoing ESD for colorectal neoplasms were enrolled. The discontinuation of anticoagulants was minimized according to recent guidelines. After the ESD, post-ESD ulcers were prophylactically closed using endoclips. The primary end-point was the incidence of delayed bleeding. The sample size was 45 lesions, and prophylactic clip closure was considered effective when the upper limit of the 90% confidence interval (CI) for delayed bleeding did not exceed 20%. RESULTS: Forty-five lesions were used, and three were excluded. Complete closure was achieved in 41/42 lesions (97.6%). The overall delayed bleeding rate was low, at 4.9% (2/41; 90% [CI] 0.8-14.5), which was significantly lower than that at the prespecified threshold of 20% (P = 0.007). The median closure procedure time was 17 min, and the median number of clips was nine. No massive delayed bleeding requiring transfusion, interventional radiology, or surgery was observed, and no thromboembolic events were observed. CONCLUSION: Prophylactic clip closure may reduce the risk of delayed bleeding following colorectal ESD in patients receiving anticoagulants. TRIAL REGISTRATION: UMIN Clinical Trial Registry (UMIN000036734).

Efficacy of chemotherapy for older patients with gastric cancer: a multicenter retrospective cohort study.

BACKGROUND: Gastric cancer is one of the leading causes of malignant disease-related mortality, worldwide. With the use of recently developed anti-tumor agents, the prognoses of patients with unresectable gastric cancer are improving. However, the development of an aggressive treatment strategy for older patients (OPs) remains under debate due to concerns regarding treatment feasibility or patient frailty. We aimed to elucidate whether aggressive chemotherapy has survival benefits for OPs with advanced gastric cancer. METHODS: We analyzed consecutive patients diagnosed with inoperable advanced gastric cancer across seven hospitals from August 2007 to July 2015. We defined OPs as patients aged 75 years or older and compared their survival rates with those of non-older patients (NPs). RESULTS: A total of 256 OPs and 425 NPs were enrolled. Of the OPs, 152 patients received chemotherapy and 104 patients received best supportive care (BSC). In contrast, among the NPs, 375 patients received chemotherapy and 50 patients received BSC. There was no significant difference of the median survival time between OPs and NPs in the response to BSC (61 vs 43 days) or chemotherapy (312 vs 348 days). Combination chemotherapy significantly improved survival compared to monotherapy in both OPs and NPs groups (382 vs 253 days in OPs, 381 vs 209 days in NPs). Good performance status, combination therapy, and male, but not age, were significant independent prognostic factors. CONCLUSION: When the performance status of a gastric cancer patient is good, active chemotherapy may improve survival, regardless of age.

[Anaphylactic shock secondary to the use of macrogol 4000 as a bowel cleanser:a case report].

A 44-year-old man was administered Niflec® containing macrogol 4000 as a bowel cleanser for colonoscopic examination. Immediately after ingestion, he experienced oral cavity discomfort and nasal congestion, followed by acute urticaria and presyncope. His systolic blood pressure and peripheral capillary oxygen saturation dropped to 66mmHg and 89%, respectively. Fluid infusion, as well as steroid and epinephrine administration, improved his symptoms. Skin prick tests were then performed using Niflec®, macrogol 4000, and Actosin® ointment (containing macrogol 4000), all of which were positive. Therefore, the patient was diagnosed with anaphylactic shock caused by macrogol 4000 included in Niflec®. Macrogol present in bowel cleansers used for colonoscopy rarely causes anaphylactic shock. However, clinicians need to be mindful of this risk. Prompt and appropriate treatment is needed should this condition occur.

Gastric endoscopic submucosal dissection under steady pressure automatically controlled endoscopy (SPACE); a multicenter randomized preclinical trial.

BACKGROUND: Steady pressure automatically controlled endoscopy (SPACE) is a new modality that eliminates on-demand insufflation but enables automatic insufflation in the gastrointestinal tract. Though its use in porcine esophageal ESD was reported to be promising, its applicability and potential effectiveness to gastric procedures have not been evaluated. OBJECTIVE: The aims were (1) to evaluate feasibility and safety of SPACE in the stomach, and (2) to assess its potential advantages over conventional endoscopy in preventing "blind insufflation"-related complications. DESIGN: A multicenter randomized preclinical animal study. SETTING: Laboratories at three universities. INTERVENTIONS: Experiment 1: Gastric ESD was attempted in the swine (n = 17), under either SPACE or manual insufflation. Experiment 2: Gastroscopy was performed for 10 min in the perforated stomach (n = 10) under either SPACE or manual insufflation. MAIN OUTCOME MEASUREMENTS: Experiment 1: ESD time, energy device activation time, number of forceps exchanges, specimen size, en block resection rate, vital signs and any intraoperative adverse events. Experiment 2: Intra-gastric and intra-abdominal pressures, vital signs, and any adverse events. RESULTS: Experiment 1: Gastric ESD was completed in all animals. ESD time tended to be shorter in SPACE than in the control, though the difference was not significant (p = 0.18). Experiment 2: Although both intra-gastric and intra-abdominal pressures remained within preset values in SPACE, they showed excessive elevation in control. LIMITATIONS: An animal study with small sample size. CONCLUSIONS: SPACE is feasible and safe for complicated and lengthy procedures such as gastric ESD, and is potentially effective in preventing serious consequences related to excessive blind insufflation.

Lymph node enlargement after definitive chemoradiotherapy for clinical stage I esophageal squamous cell carcinoma.

BACKGROUND: Chemoradiotherapy (CRT) is an effective modality for stage I esophageal squamous cell carcinoma (ESCC). However, salvage treatments are often required even if complete response (CR) has been achieved. To this end, it is important to accurately diagnose lymph node or other organ metastatic recurrences. Note that lymph node enlargements (except metastatic recurrence) are often detected during the follow-up period after CRT. The purpose of this study was to elucidate the clinical characteristics of lymph node enlargement after CRT. METHODS: In this retrospective cohort study, patients diagnosed with stage I (T1 [submucosal invasion] N0M0) ESCC were treated with cisplatin and 5-fluorouracil concurrently with radiotherapy. A total of 55 patients were enrolled in the study from February 2006 to August 2011. RESULTS: The median follow-up period was 46 months. The 3-year overall and progression-free survival rates were 90.7% and 71.2%, respectively, and the CR rate was 87.2% (48/55). Nine of the 48 CR patients were finally diagnosed with recurrences, including 7 lymph node metastases and 2 local recurrences. Lymph node enlargement was initially identified in 20 of the total 55 patients during the follow-up; 9 patients were finally diagnosed with lymph node recurrence, whereas 11 patients had benign reactive lymph node enlargement. CONCLUSION: The present study demonstrated the high incidence of enlarged lymph nodes after CRT for stage I ESCC. It is important to accurately distinguish between benign lymph node enlargement and recurrent lymph nodes to avoid unnecessary salvage treatments.

Utility and advantage of the unroofing technique for gastrointestinal subepithelial tumors: A multicenter retrospective cohort study.

Background and aim: Various techniques for direct biopsy from gastrointestinal subepithelial tumors (SETs) have been reported, although no standard method has been established. A common feature of these techniques is the removal of overlaying mucosa to enable direct biopsies from the SETs. These methods have been synthesized under the collective term "unroofing technique". We conducted a multicenter retrospective study to assess its efficacy and identify potential complications. Methods: This study was conducted in 10 hospitals and involved all eligible patients who underwent unroofing techniques to obtain biopsies for gastrointestinal SETs between April 2015 and March 2021. The primary endpoint was the diagnostic accuracy of the unroofing technique, and the secondary endpoints were the incidence of adverse events and the factors contributing to the accurate diagnosis. Results: The study included 61 patients with 61 gastrointestinal SETs. The median tumor size was 20 mm, and the median procedure time was 38 min, with 82% successful tumor exposure. The rate of pathological diagnosis was 72.1%. In 44 patients with a pathological diagnosis, two showed discrepancies with the postresection pathological diagnosis. No factors, including facility experience, organ, tumor size, or tumor exposure, significantly affected the diagnostic accuracy. There was one case of delayed bleeding and two cases of perforation. Conclusion: The diagnostic yield of the unroofing technique was acceptable. The unroofing technique was beneficial regardless of institutional experience, organ, tumor size, or actual tumor exposure.

Adiponectin negatively correlates with alcoholic and non-alcoholic liver dysfunction: Health check-up study of Japanese men.

AIM: Central obesity, insulin resistance and alcohol consumption are thought to be major risk factors for fatty liver formation. Adiponectin (APN) prevents fatty liver formation, and its serum levels are lower in subjects with central obesity and/or insulin resistance. The aim of this study was to explore the association among serum APN levels, central obesity, insulin resistance and liver dysfunction with or without fatty liver classified by alcohol consumption in healthy subjects. METHODS: A total of 5588 Japanese male subjects who underwent a health check-up were classified into three groups according to alcohol consumption: non- or light drinkers (15 g/day ≥ ethanol); mild drinkers (15 g/day < ethanol ≤ 30 g/day); and moderate- or heavy drinkers (30 g/day < ethanol). Central obesity and insulin resistance were assessed by waist circumference (WC) and Homeostasis Model of Assessment - Insulin Resistance (HOMA-IR), respectively. RESULTS: WC was significantly increased, while HOMA-IR was significantly decreased according to the extent of alcohol consumption. Serum alanine aminotransferase levels were significantly lower and serum APN levels were significantly higher in mild drinkers than in the other two groups. Multiple linear regression analysis showed that serum APN level served as the significant and independent determinant for liver dysfunction in the subjects with fatty liver, irrespective of alcohol consumption. However, WC became a non-significant determinant of liver dysfunction as alcohol consumption increased. CONCLUSION: Hypoadiponectinemia is a significant determinant for steatotic dysfunction for all levels of alcohol consumption, but central obesity was not a significant determinant for alcoholic fatty liver-induced liver dysfunction.

Plasmablastic lymphoma occurring in ulcerative colitis during treatment with immunosuppressive therapy.

A 53-year-old man who had a history of ulcerative colitis (UC) for 2 years underwent colonoscopy as regular follow-up. The results showed an elevated lesion in the descending colon, which was diagnosed as plasmablastic lymphoma (PBL) based on pathological findings. In situ hybridization for the Epstein-Barr virus-encoded RNA probe was positive. Fluorescence in situ hybridization revealed rearrangement of the MYC gene. He had been taking prednisolone, 5-aminosalicylic acid, azathiopurine, and ustekinumab at the diagnosis of PBL and had multiple prior therapies for UC including infliximab, tacrolimus, and tofacitinib due to steroid dependence. PBL is a rare aggressive B cell lymphoma initially described in the oral cavity of human immunodeficiency virus positive patients and it is suspected to have an association with immunocompromised status of patients. The number of cases of PBL in inflammatory bowel disease (IBD) patients is extremely rare. All these patients were administered immunosuppressive therapy including thiopurines or biologics. IBD patients with immunosuppressive therapy have a higher potential for developing lymphoproliferative disorders. Clinicians should be aware of the risk of lymphoma, including PBL.

Protective role of adiponectin against ethanol-induced gastric injury in mice.

Adiponectin is an anti-inflammatory molecule released from adipocytes, and serum adiponectin concentrations are reduced in obesity. We previously reported that gastric erosion occurs in association with obesity and low serum adiponectin levels. In the present study, we examined adiponectin-knockout (APN-KO) mice to elucidate the role of adiponectin in gastric mucosal injury. Gastric injury was induced by oral administration of ethanol in wild-type (WT) and APN-KO mice. Ethanol treatment induced severe gastric injury in APN-KO mice compared with WT mice. In APN-KO mice, increased apoptotic cells and decreased expression of prostaglandin E(2) (PGE(2)) were detected in the injured stomach. We next assessed the effect of adiponectin on the cellular response to ethanol treatment and wound repair in rat gastric mucosal cells (RGM1). Adiponectin induced the expression of PGE(2) and cyclooxygenase 2 (COX-2) in ethanol-treated RGM1 cells. RGM1 cells exhibited efficient wound repair accompanied by increased PGE(2) expression in the presence of adiponectin. Coadministration of adiponectin with celecoxib, a COX-2 inhibitor, inhibited efficient wound repair. These findings indicate that adiponectin has a protective role against ethanol-induced gastric mucosal injury in mice. This effect may be partially mediated by the efficient wound repair of epithelial cells via increased PGE(2) expression.

Lower serum level of adiponectin is associated with increased risk of endoscopic erosive gastritis.

BACKGROUND: Obesity is recently known as a risk factor for endoscopic gastritis. Adiponectin is an anti-inflammatory cytokine secreted from fat tissue, and its serum concentrations are reduced in obesity. The relation between adiponectin and gastritis remains unclear. AIMS: The aim of this study was to determine whether lower serum adiponectin level is associated with the risk of endoscopic gastritis. METHODS: We analyzed medical records of participants of a routine health check-up examination. Association among endoscopic findings, serum adiponectin level, and other clinical factors including age, sex, alcohol habit, smoking habit, body mass index (BMI), blood pressure, cholesterol, triglyceride, glucose, and insulin were investigated. Endoscopic erosive gastritis was defined as a flat or minimally depressed white spot surrounded by a reddish area or small elevation with central umbilications mimicking octopus' suckers. RESULTS: A total of 2,400 participants were enrolled. BMI was significantly higher in gastritis-positive participants than in gastritis-negative participants. Serum adiponectin levels were significantly lower in gastritis-positive participants than in gastritis-negative participants. Multivariate logistic regression analysis revealed that lower serum adiponectin level (OR 0.96; 95% CI 0.93-0.99), smoking (OR 0.50; 95% CI 0.30-0.80), higher blood pressure (OR 1.02; 95% CI 1.01-1.03), and duodenitis (OR 1.8; 95% CI 1.00-3.09) were significantly associated with endoscopic erosive gastritis. CONCLUSIONS: Lower serum level of adiponectin may increase the risk of endoscopic erosive gastritis, independently of BMI. Our findings facilitate further study to clarify the role of hypoadiponectinemia in erosive gastritis.

Short-term outcomes of endoscopic submucosal dissection (ESD) for early gastric neoplasm: multicenter survey by osaka university ESD study group.

BACKGROUND: Endoscopic submucosal dissection (ESD) was developed for en bloc removal of large and flat gastrointestinal tract neoplasms. In Japan, ESD is performed under conscious sedation. The risks for sedation-related complications of ESD, such as postoperative pneumonia, have not been evaluated. The aim of this study was to evaluate the incidence of postoperative pneumonia after ESD in a multicenter survey. PATIENTS AND METHODS: A total of 1188 patients with upper gastric neoplasms treated with ESD in nine hospitals were enrolled from May 2003 to September 2008. The en bloc resection rates and complications (bleeding, perforation, and postoperative pneumonia) were assessed. The correlations between the clinical variables and complications were investigated using logistic regression models. RESULTS: The en bloc resection rate was 95.3%. Bleeding, perforation, and pneumonia occurred in 37 (3.1%), 49 (4.1%), and 19 (1.6%) patients, respectively. Univariate analysis indicated that procedure time, but not specimen size, or patient age, or sex, was significantly related to bleeding and perforation. The incidence of pneumonia was higher in patients with ulceration, older patients (≥75years), and those with a long procedure duration (≥5h). CONCLUSION: The incidence of pneumonia, but not perforation and bleeding, after ESD, is high in older patients (≥75years). Special care should be taken with older patients undergoing ESD to minimize the risk of postoperative pneumonia.

[Bronchogenic cyst in the abdomen--a case report].

A man in his thirties with epigastric pain was referred to our hospital for detailed examinations. Abdominal computed tomography showed an abdominal cystic lesion with a longest dimension of 7 cm, located behind the stomach. Endoscopic ultrasonography through the stomach showed a cystic lesion and the wall of the lesion revealed continuity to the proper muscle layer of the gastric wall. Therefore, gastric duplication was suspected and the cystic lesion was resected because of the possibility of malignancy and also for a definitive diagnosis. The cystic lesion consisted of columnar ciliated epithelium, seromucous glands, smooth muscle and cartilage and was diagnosed as a bronchogenic cyst. Bronchogenic cysts are sometimes encountered in the thoracic or mediastinal area, but abdominal bronchogenic cysts, such as the present case, are extremely rare.

Community-acquired fulminant Clostridioides (Clostridium) difficile infection by ribotype 027 isolate in Japan: a case report.

BACKGROUND: Clostridioides (Clostridium) difficile infection (CDI) has become an increasingly significant disease not only as healthcare-associated infection, but also as community-acquired (CA) infection worldwide. CDI caused by the NAP1/BI/027 strain is reported to be more severe, difficult to cure, and frequently associated with recurrences in North America and Europe. CASE PRESENTATION: A 68-year-old woman was referred to our hospital for continuous lower abdominal pain 4 weeks after eradication therapy against Helicobacter pylori. While she was treated with fasting on the suspicion of ischemic colitis, she experienced septic shock. Emergent subtotal proctocolectomy revealed fulminant pseudomembranous C. difficile colitis. The C. difficile isolate recovered from the patient was identified as ribotype 027, which has been reported to be uncommon in Japan. CONCLUSION: We report a rare case of CA fulminant pseudomembranous colitis caused by ribotype 027 C. difficile after H. pylori eradication therapy.

Renal Dysfunction is an Independent Risk Factor for Rebleeding After Endoscopic Hemostasis in Patients with Peptic Ulcer Bleeding.

BACKGROUND: Despite the progress in endoscopic hemostasis and pharmacological treatment, the mortality rate of peptic ulcer bleeding remains at 5-10%. Rebleeding after peptic ulcer bleeding is believed to be a risk factor for mortality. This study aimed to evaluate whether renal dysfunction is a predictor of rebleeding after endoscopic hemostasis in patients with peptic ulcer bleeding. METHODS: In this retrospective study, consecutive patients with peptic ulcer bleeding who underwent endoscopic hemostasis at our Hospital from January 2010 to December 2018 were enrolled. The relationship between rebleeding within 30 days after endoscopic hemostasis and the patients' admission and endoscopic characteristics were analyzed using univariate and multivariate regression models. RESULTS: Out of 274 patients with peptic ulcer bleeding, 17 (6.2%) patients experienced rebleeding. In the analysis of the patients' admission characteristics, estimated glomerular filtration rate (eGFR) < 30 mL/min/1.73 m2 was an independent risk factor for rebleeding (odds ratio 4.77, 95% confidence interval 1.168-18.211, p = 0.03). Patients with eGFR < 15 mL/min/1.73 m2 with or without hemodialysis had the highest rebleeding rate at 36.8%. With respect to endoscopic characteristics, the rate of rebleeding was associated with combination therapy (p < 0.0001) and active bleeding (p = 0.03). CONCLUSION: Renal dysfunction might be an independent risk factor for rebleeding after endoscopic hemostasis in patients with peptic ulcer bleeding.

Lack of adiponectin promotes formation of cholesterol gallstones in mice.

Plasma adiponectin levels are reduced in obese people, and hypoadiponectinemia is recently reported to associate with cholesterol gallstone formation in human. The aim of this study was to examine the role of adiponectin in gallstone formation using adiponectin knockout mice. We analyzed male knockout and C57BL6J mice fed normal or lithogenic diet for 6 weeks. On lithogenic diet, the prevalence rate of gallstone was significantly greater in knockout mice than C57BL6J mice. The molar percentages of beta and omega-muricholic acid were significantly higher and hepatic sterol 12 alpha-hydroxylase expression (cyp8b1) was significantly lower in knockout mice than C57BL6J mice fed normal diet. The bile apolipoprotein A-I protein levels were decreased in knockout mice. Histological examination showed gallbladder wall thickening and accumulation of glycoprotein in the gallbladder of knockout mice. Gallbladder phospholipase A2-IVA expression was significantly higher in knockout mice than in C57BL6J mice fed lithogenic diet. Our results indicate that lack of adiponectin promotes gallstone formation in mice.

Salvage cystic duct anastomosis using a magnetic compression technique for incomplete bile duct reconstruction in living donor liver transplantation.

In living donor liver transplantation (LDLT), bile duct reconstruction is often technically demanding due to the frequently anomalous anatomy of the bile duct, as well as the high incidence of biliary complications. A bile duct branch may also be accidentally left without anastomosis at the time of LDLT and found to be obstructed after surgery. Surgical revision for such cases is sometimes not feasible because of the invasiveness of the procedure. We report a case in which a bile duct branch was intentionally left without anastomosis and was later successfully anastomosed to the cystic duct stump using a magnetic compression anastomosis (MCA) technique. A combination of the MCA technique and cystic duct anastomosis is life-saving in certain situations and should be considered as the treatment of choice.

Phase I trial of gemcitabine dose escalation with concurrent radiotherapy for patients with locally advanced pancreatic cancer.

AIM: The safety and efficacy, and the dose-limiting toxicity (DLT) of the chemotherapeutic agent gemcitabine administered in conjunction with radiotherapy in patients with locally advanced pancreatic cancer are not yet established. Here, we evaluated the safety and efficacy, DLT, and maximum tolerated dose of gemcitabine with concurrent radiotherapy in patients with unresectable locally advanced pancreatic cancer. Tumor response and time to progression were also assessed. PATIENTS AND METHODS: Patients with previously untreated pancreatic cancer (n = 12) received gemcitabine intravenously on days 1, 8, and 15. Concurrent radiation therapy was initiated on day 1 (40 Gy in 2 Gy/day x 20 fractions, days 1-5, 8-12, 15-19, 22-26). Patients received limited-field irradiation with three-dimensional radiotherapy. Dose escalation included dose levels 1-3 (gemcitabine 400, 600, and 800 mg/m(2)). RESULTS: No patient developed DLT in this study. Of the 12 patients, there were 11 sustained responses, 0 partial responses, and 1 progressive disease. Two patients with a sustained response underwent surgery after re-evaluation. The median progression-free survival was 8 months, not including the patients that underwent surgery. CONCLUSION: Weekly gemcitabine at a dose of 800 mg/m(2) with concurrent radiation therapy in patients with locally advanced pancreatic cancer was well tolerated. and IAP.

[Collision tumor of a carcinoid and carcinoma in the rectum].

A man in his seventies visited our hospital due to positive a fecal occult blood test. Colonoscopy showed a submucosal tumor in the rectum covered with reddish and irregular mucosa. Pathological examination of the biopsy specimen revealed well differentiated adenocarcinoma. The tumor was resected, and pathological examination showed carcinoid and adenocarcinoma components coexisting and mixed with each other. Because a previous colonoscopy had shown a submucosal tumor with a smooth surface, this case was diagnosed as a collision tumor of adenocarcinoma which developed on a carcinoid.

Effect of anticoagulants on the risk of delayed bleeding after colorectal endoscopic submucosal dissection.

Background and study aims In patients receiving antithrombotic therapy, the risks of delayed bleeding after endoscopic procedures for gastrointestinal neoplasms become a major problem. Few reports have shown the effects of delayed bleeding in patients taking anticoagulants after colorectal endoscopic submucosal dissection (ESD). This study aimed to evaluate the delayed bleeding events after colorectal ESD in patients receiving anticoagulant therapy. Patients and methods We retrospectively analyzed 87 patients taking anticoagulants who underwent colorectal ESD from April 2012 to December 2017 at 13 Japanese institutions participating in the Osaka Gut Forum. Among these patients, warfarin users were managed with heparin bridge therapy (HBT), continued use of warfarin, a temporary switch to direct oral anticoagulation (DOAC), or withdrawal of warfarin, and DOAC users were managed with DOAC discontinuation with or without HBT. We investigated the occurrence rate of delayed bleeding and compared the rates between warfarin and DOAC users. Results The delayed bleeding rate was 17.2 % among all patients. The delayed bleeding rate was higher in DOAC users than in warfarin users (23.3 % vs. 11.4 %, P  = 0.14), although no statistically significant difference was observed. In DOAC users, the delayed bleeding rates for dabigatran, rivaroxaban, apixaban, and edoxaban users appeared similar (30 %, 18.2 %, 22.2 %, and 25 %, respectively). The onset of delayed bleeding in both warfarin and DOAC users was late, averaging 6.9 and 9.4 days, respectively. Conclusions Among patients taking anticoagulants, the risk of delayed bleeding after colorectal ESD was relatively high and the onset of delayed bleeding was late.

Adiponectin prevents progression of steatohepatitis in mice by regulating oxidative stress and Kupffer cell phenotype polarization.

AIM: We reported previously that hypoadiponectinemia enhances hepatic oxidative stress and accelerates progression of nonalcoholic steatohepatitis (NASH) in mice. However, the precise mechanism and preventive effects of adiponectin on NASH remain unclear. The aim of this study was to examine the effects of adiponectin on steatohepatitis using adiponectin-knockout (KO) mice and adenovirus-mediated adiponectin expression system. METHODS: We used male KO mice and C57BL6/J (WT) mice fed methionine choline-deficient (MCD)-diet as a steatohepatitis model. Liver histology, hepatic oxidative stress markers, and hepatic gene expression levels were investigated. In addition, Hepa 1-6 cells, a mouse liver cell line, were cultured with or without recombinant adiponectin, and gene expressions were investigated by real-time RT-PCR. RESULTS: After 2-week feeding of MCD diet, hepatic steatosis was enhanced and plasma alanine aminotransferase elevated in KO mice than in WT mice. In KO mice liver, thiobarbituric acid reactive substances increased, glutathione levels decreased, and mRNA expression levels of antioxidant enzymes (catalase, superoxide dismutase-1) downregulated. Adenovirus-mediated adiponectin expression prevented these changes in KO mice. Moreover, Kupffer cell infiltration was enhanced and mRNA levels of anti-inflammatory M2 macrophage markers (interleukin-10, arginase-1) were decreased in KO mice liver. In the in vitro study, adiponectin significantly increased catalase gene expression in Hepa 1-6 cells. CONCLUSIONS: Lack of adiponectin enhanced, and adiponectin administration prevented steatohepatitis progression in mice. These changes were due to the anti-oxidative effects of adiponectin, and its effects on Kupffer cells recruitment and phenotype polarization. Augmentation of adiponectin effects could be a useful preventive approach for NASH progression.