Gelsolin impairs barrier function in pancreatic ductal epithelial cells by actin filament depolymerization in hypertriglyceridemia-induced pancreatitis in vitro.

Gelsolin (GSN) is a calcium-regulated actin-binding protein that can sever actin filaments. Notably, actin dynamics affect the structure and function of epithelial barriers. The present study investigated the role of GSN in the barrier function of pancreatic ductal epithelial cells (PDECs) in hypertriglyceridemia-induced pancreatitis (HTGP). The human PDEC cell line HPDE6-C7 underwent GSN knockdown and was treated with caerulein (CAE) + triglycerides (TG). Intracellular calcium levels and the actin filament network were analyzed under a fluorescence microscope. The expression levels of GSN, E-cadherin, nectin-2, ZO-1 and occludin were evaluated by reverse transcription-quantitative polymerase chain reaction and western blotting. Ultrastructural changes in tight junctions were observed by transmission electron microscopy. Furthermore, the permeability of PDECs was analyzed by fluorescein isothiocyanate-dextran fluorescence. The results revealed that CAE + TG increased intracellular calcium levels, actin filament depolymerization and GSN expression, and increased PDEC permeability by decreasing the expression levels of E-cadherin, nectin-2, ZO-1 and occludin compared with the control. Moreover, changes in these markers, with the exception of intracellular calcium levels, were reversed by silencing GSN. In conclusion, GSN may disrupt barrier function in PDECs by causing actin filament depolymerization in HTGP in vitro.

SphK1-driven autophagy potentiates focal adhesion paxillin-mediated metastasis in colorectal cancer.

Invasion and metastasis are the main causes of colorectal cancer (CRC)-related death. Accumulating evidence suggested that sphingosine kinase 1 (SphK1) promoted the metastasis of CRC and autophagy played an important role in SphK1 promoting the metastasis of malignancy. However, the mechanism by which SphK1-driven autophagy promotes invasion and metastasis in CRC remains to be clarified. In the present study, immunohistochemical detection showed the expression of SphK1 and paxillin was higher in human CRC tissues than those of normal colorectal mucosal tissues, they were both associated with TNM staging, lymphatic, and distance metastasis. In addition, study of in situ tumor transplantation model in nude mice showed that the suppression of SphK1 inhibited the growth of colonic orthotopic implantation tumors and the expression of paxillin, p-paxillin, LC3 in the tumor. So, SphK1 may promote CRC metastasis via inducing the expression of paxillin expression and its phosphorylation, in vivo. Furthermore, results of CCK8 assay, transwell and wound healing assays showed that SphK1 promoted the viability, invasion, and metastasis of CRC cells. Transmission electron microscopy detection showed that SphK1 is the key factor in autophagy induction in CRC cells. Moreover, western blot examination indicated that the expression of LC3Ⅱ/Ⅰ, paxillin, p-paxillin, MMP-2, and vimentin was enhanced in SphK1-overexpressed CRC cells and suppressed in SphK1 knockdown CRC cells, meanwhile, the expression of E-cadherin was suppressed in SphK1-overexpressed CRC cells and enhanced in SphK1 knockdown CRC cells. Suppression of autophagy by 3MA reversed the expression of paxillin and its phosphorylation in SphK1-overexpressed CRC cells, indicated that SphK1-driven autophagy induced the expression of paxillin and its phosphorylation in CRC cells. Together, these findings reveal that SphK1-driven autophagy may promote the invasion and metastasis of CRC via promoting the expression of focal adhesion paxillin and its phosphorylation.

Cronkhite-Canada syndrome with steroid dependency: A case report.

BACKGROUND: Cronkhite-Canada syndrome (CCS) is a rare nonhereditary disease characterized by chronic diarrhoea, diffuse gastrointestinal polyposis and ectodermal manifestations. The lethality of CCS can be up to 50% if it is untreated or if treatment is delayed or inadequate. More than 35% of the patients do not achieve long-term clinical remission after corticosteroid administration, with relapse occurring during or after the cessation of glucocorticoid use. The optimal strategy of maintenance therapy of this disease is controversial. CASE SUMMARY: A 47-year-old man presented to the hospital with a 3-mo history of frequent watery diarrhoea, accompanied by macular skin pigmentation that included the palms and soles, and onychodystrophy of the fingernails and toenails. Gastroscopy and colonoscopy revealed numerous polyps in the stomach and colon. After other possibilities were ruled out by a series of examinations, CCS was diagnosed and treated with prednisone. The patient took prednisone for more than 1 year before achieving complete resolution of his symptoms and endoscopic findings. The patient was then given prednisone 5 mg/d for 6 mo of maintenance therapy. With clinical improvement and polyp regression, prednisone was discontinued. Eight mo after the discontinuation of prednisone, the diarrhoea and gastrointestinal polyps relapsed. Therefore, the patient was given the same dose of prednisone, and complete remission was achieved again. CONCLUSION: It is necessary to extend the duration of prednisone maintenance therapy for CCS. Prednisone is still effective when readministered after relapse. Surveillance endoscopy at intervals of 1 year or less is recommended to assess mucosal disease activity.

Ghrelin inhibits IKKß/NF-κB activation and reduces pro-inflammatory cytokine production in pancreatic acinar AR42J cells treated with cerulein.

BACKGROUND: Previous studies have provided conflicting results regarding whether the serum ghrelin concentration can reflect the severity of acute pancreatitis (AP). The present study examined the correlation between the serum ghrelin concentration and AP severity in animal models and investigated whether altered ghrelin expression in pancreatic acinar cells influences IKKß/NF-κB signaling and pro-inflammatory cytokine production. METHODS: Mild or severe AP was induced in rats by intraperitoneal injection of cerulein or retrograde cholangiopancreatic duct injection of sodium taurocholate, respectively. After successful model induction, serum ghrelin, tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6) concentrations were determined by enzyme-linked immunosorbent assay, and IKKß/NF-κB activation was assessed by immunohistochemistry. Subsequently, stable overexpression or knockdown of ghrelin in AR42J cells was achieved by lentiviral transfection. After transfected cells and control cells were treated with cerulein for 24 h, the TNF-α and IL-1ß levels in the supernatants were determined by enzyme-linked immunosorbent assay, and the expression levels of p-p65, IKKß, and p-IKKß were detected by Western blotting. RESULTS: In rat AP models, AP severity was correlated with increased IKKß/NF-κB activation, pro-inflammatory cytokine production, and ghrelin secretion. The levels of pro-inflammatory cytokines TNF-α and IL-1ß as well as IKKß/NF-κB signaling activity were increased upon knockdown of ghrelin in the AP acinar cell model and decreased with ghrelin overexpression. CONCLUSIONS: Serum ghrelin is related to the severity of AP. Ghrelin may play a protective role in the pathogenesis of AP by inhibiting the pro-inflammatory cytokines and the activation of the IKKß/NF-κB signaling pathway.

Microbial Profiles and Risk Factors of Preexisting Biliary Infection in Patients with Therapeutic Endoscopy.

BACKGROUND: The bile infection may already exist before the administration of an interventional procedure, despite no clinical manifestations of cholangitis detected. Blood cultures remained negative even in more than half of the febrile cases with cholangitis. Risk factors associated with bacterial growth in bile before the intervention are not well defined. To establish the bacterial profiles isolated from the bile samples and to identify risk factors for bacterial colonization in the bile system. METHODS: Individuals who underwent endoscopic retrograde cholangiopancreatography (ERCP) interventions were enrolled. Bile samples were aspirated and were immediately transferred into a sterile tube for storage. RESULTS: Positive bile cultures were detected in 363 (38.0%) of 956 patients, including 322 benign diseases and 41 malignances. Of 363 positive cases, 351 (96.7%) were monoinfection and 12 (3.3%) multi-infection. Escherichia coli were the most common Gram-negative bacteria (210, 56.0%), followed by Klebsiella pneumoniae (45, 12.0%). Enterococcus faecalis represented the most common Gram-positive microorganism (19, 5.07%), while Candida albicans (11, 2.93%) were the dominant fungi. Klebsiella pneumoniae were more frequently detected in malignant diseases (P = 0.046). Age, previous ERCP history or OLT history, and CBD diameter were independent risk factors for positive cultures (P < 0.05) while preoperative jaundice drug therapy was the protective factor for bile infection (P < 0.05). CONCLUSION: Monomicrobial infection was dominant among all infections, and Klebsiella pneumoniae strains were more frequently isolated from patients with malignant diseases. To effectively manage patients who are at a high risk for bile infection, a detailed diagnosis and treatment plan for each case should be prepared.

Role of Wnt/ß-catenin pathway agonist SKL2001 in Caerulein-induced acute pancreatitis.

The goal of this study was to clarify the protective role of the Wnt/ß-catenin pathway agonist SKL2001 in a rat model of Caerulein-induced acute pancreatitis. AR42J cells and rats were divided into 4 groups: control, Caerulein, SKL2001 + Caerulein, and SKL2001 + control. Cell apoptosis was examined using flow cytometry. Hematoxylin-eosin staining was performed to observe pathological changes in pancreatic and small intestinal tissues. Inflammatory cytokines were detected by enzyme-linked immunosorbent assay (ELISA), while genes related to the Wnt/ß-catenin pathway were quantified using quantitative real-time PCR. In vitro results showed that Caerulein promoted cell necrosis, inhibited the Wnt/ß-catenin pathway, and increased the level of inflammatory cytokines. However, SKL2001 reduced cell necrosis and inflammatory cytokines and activated the Wnt/ß-catenin pathway. Additionally, in vivo results demonstrated the accumulation of fluid (i.e., edema), hemorrhage, inflammation and necrosis of the pancreatic acini occurred 6 h after the final Caerulein induction, with the damage reaching a maximal level 12 h after the final Caerulein induction; meanwhile, the Wnt/ß-catenin pathway was evidently inhibited with an enhanced level of inflammatory cytokines. The aforementioned damage was further aggravated 12 h later. Nevertheless, the pancreatic and small intestinal tissue damages were alleviated in Caerulein-induced rats treated with SKL2001. In conclusion, activation of the Wnt/ß-catenin pathway could inhibit Caerulein-induced cell apoptosis and inflammatory cytokine release, thus improving pancreatic and intestinal damage in rats with acute pancreatitis.

Double-balloon enteroscopy in diagnosis of small intestinal disease / 中国内镜杂志

Objective To explore the clinical value of double-balloon enterocopy (DBE) in diagnosis of small intestinal diseases. Methods The clinical and endoscope image data of 231 patients with suspected small bowel disease who underwent DBE from January 2008 to May 2016 were analyzed. Result 231 patients received 257 times of DBE examination, 112 of them were performed by oral and 93 by anal route, 26 patients were underwent by both approaches. The detection rate of intestine diseases was 64.9% (150/231), include 33 cases (14.3%) of nonspecific enteritis, 27 cases (11.7%) of crohn's disease, 19 cases (8.2%) of ulcer, 13 cases (5.6%) of intestinal vascular malformation, 12 cases (5.2%) of small intestinal stromal tumor. The lesion detection rate in obscure abdominal pain and obscure gastrointestinal bleeding were 59.6% (62/104) and 67.0% (63/94). In all patients, there were 1 case of small bowel perforation, the remaining patients had no serious complications such as bleeding and perforation. Conclusion The positive detection rate of double-balloon enteroscopy examination is high, and the double-balloon enteroscopy examination is relatively safe. So, double-balloon enterscopy examination has high diagnostic value for detecting small intestine diseases.

Double-balloon enteroscopy in diagnosis of small intestinal disease / 中国内镜杂志

Objective To explore the clinical value of double-balloon enterocopy (DBE) in diagnosis of small intestinal diseases. Methods The clinical and endoscope image data of 231 patients with suspected small bowel disease who underwent DBE from January 2008 to May 2016 were analyzed. Result 231 patients received 257 times of DBE examination, 112 of them were performed by oral and 93 by anal route, 26 patients were underwent by both approaches. The detection rate of intestine diseases was 64.9% (150/231), include 33 cases (14.3%) of nonspecific enteritis, 27 cases (11.7%) of crohn's disease, 19 cases (8.2%) of ulcer, 13 cases (5.6%) of intestinal vascular malformation, 12 cases (5.2%) of small intestinal stromal tumor. The lesion detection rate in obscure abdominal pain and obscure gastrointestinal bleeding were 59.6% (62/104) and 67.0% (63/94). In all patients, there were 1 case of small bowel perforation, the remaining patients had no serious complications such as bleeding and perforation. Conclusion The positive detection rate of double-balloon enteroscopy examination is high, and the double-balloon enteroscopy examination is relatively safe. So, double-balloon enterscopy examination has high diagnostic value for detecting small intestine diseases.

Melatonin reduces inflammation and recovers endogenous ghrelin in acute necrotizing pancreatitis in rats.

The present study aimed to evaluate the therapeutic effects of melatonin on either ghrelin secretion or gastric mucosal injury in acute necrotizing pancreatitis (ANP). ANP was induced in rats by L-arginine. Prior to L-arginine injection, the rats were pre-treated with melatonin for 30 min. Following the last injection, the animals were sacrificed at different time-points. The levels of ghrelin and melatonin in the serum and gastric tissue were detected by ELISA. Levels of tumor necrosis factor (TNF)-α, interleukin (IL)-6 and malondialdehyde (MDA) as well as total superoxide dismutase (T-SOD) activities in gastric tissue were measured. In rats with ANP, acute gastric injury was observed, and the levels of MDA, SOD, TNF-α and IL-6 were significantly increased. The melatonin levels in serum or gastric tissue peaked at 6 h and returned to normal levels at 12 h after melatonin was administered. However, ghrelin remained at low levels during the first 12 h, but it recovered at 24 h and continued increasing, while the levels of oxidative stress damage and activity of inflammatory factors were decreased. The protective effects of melatonin on acute gastric injury during the early stages of ANP may be mediated through anti-oxidative and anti-inflammatory activities, while at advanced stages of ANP, it may be mediated through the recovered endogenous ghrelin.

Effects of ginsenoside Rh2 on growth and migration of pancreatic cancer cells.

AIM: To investigate the effects of ginsenoside Rh2 on the human pancreatic cancer cell line Bxpc-3. METHODS: The human pancreatic cancer cell line Bxpc-3 was cultured in vitro and treated with or without ginsenoside Rh2. Growth rates for Bxpc-3 cells were assessed by methyl thiazolyl tetrazolium (MTT) and colony formation assays. Cell cycle changes were analyzed by flow cytometry. Apoptosis was measured by flow cytometry and Hoechst 33258 fluorescence staining. A scratch assay and a Matrigel invasion assay were used to detect cell migration and invasion. Expression of Bax, Bcl-2, survivin, cyclin D1, matrix metalloproteinase (MMP)-2, MMP-9, cleaved caspase-3, caspase-8, and caspase-9 mRNA were determined by reverse transcriptase-polymerase chain reaction (RT-PCR). Bax, Bcl-2, survivin, cyclin D1, cleaved caspase-3, caspase-8 and caspase-9 protein levels were examined by western blotting. Expression of MMP-2 and MMP-9 proteins in culture supernatants were determined by enzyme-linked immunosorbent assay (ELISA). RESULTS: Rh2 significantly inhibited Bxpc-3 cell proliferation in a dose- and time-dependent manner, as evaluated by the MTT (P < 0.05) and colony formation assays (P < 0.05). Compared to the control group, Rh2 significantly increased the percentage of Bxpc-3 cells in the G0/G1 phase from 43.32% ± 2.17% to 71.32% ± 1.16%, which was accompanied by a decrease in S phase (from 50.86% ± 1.29% to 28.48% ± 1.18%) and G2/M phase (from 5.81% ± 1.19% to 0.20% ± 0.05%) in a dose-dependent manner (P < 0.05), suggesting that Rh2 arrested cell cycle progression at the G0/G1 phase, as measured by flow cytometry. Compared to the control group, cells treated with Rh2 showed significantly higher apoptosis ratios in a dose-dependent manner (percentage of early apoptotic cells: from 5.29% ± 2.28% to 38.90% ± 3.42% (F = 56.20, P < 0.05); percentage of late apoptotic cells: from 4.58% ± 1.42% to 36.32% ± 2.73% (F = 86.70, P < 0.05). Rh2 inhibited Bxpc-3 cell migration and invasion, as detected by scratch wound healing assay and Matrigel invasion assay [percentages of scratch wound healing for 12 h, 24 h and 48 h (control vs experimental group): 37.3% ± 4.8% vs 18.30% ± 1.65%, 58.7% ± 3.5% vs 38.00% ± 4.09% and 93.83% ± 4.65% vs 65.50% ± 4.09%, respectively; t = 6.489, t = 6.656 and t = 7.926, respectively, P < 0.05; the number of cells invading at various concentrations (0 µmol/L, 35 µmol/L, 45 µmol/L and 55 µmol/L): 81.10 ± 9.55, 46.40 ± 6.95, 24.70 ± 6.88 and 8.70 ± 3.34, respectively (F = 502.713, P < 0.05)]. RT-PCR, western blotting or ELISA showed that mRNA and protein expression of Bax, cleaved caspase-3 and caspase-9 were upregulated (P < 0.05), while mRNA and protein expression of Bcl-2, survivin, cyclin D1, MMP-2 and MMP-9 were downregulated (P < 0.05). CONCLUSION: Ginsenoside Rh2 inhibits proliferation, migration and invasion and induces apoptosis of the human pancreatic cancer cell line Bxpc-3.

Mechanisms underlying aspirin-mediated growth inhibition and apoptosis induction of cyclooxygenase-2 negative colon cancer cell line SW480.

AIM: To investigate the effects of aspirin (acetylsalicylic acid) on proliferation and apoptosis of colorectal cancer cell line SW480 and its mechanism. METHODS: Cyclooxygenase (COX)-2 negative colorectal cancer cell line SW480 was treated with aspirin at concentrations of 2.5 mmol/L, 5.0 mmol/L, 10.0 mmol/L for different periods in vitro. Anti-proliferation effect of aspirin on SW480 was detected by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Cell cycle and apoptosis were observed by flow cytometry (FCM). Transmission electron microscope (TEM) was used for morphological study. Apoptosis-associated genes were detected by immunohistochemical staining and Western blotting. RESULTS: Aspirin inhibited SW480 proliferation and induced apoptosis in a dose- and time-dependent manner. Treatment with different concentrations of aspirin significantly increased the proportions of cells at the G(0)/G(1)phase and decreased the proportions of cells at the S- and G(2)/M phases in a concentration-dependent manner. Aspirin not only induced apoptosis but also caused cell necrosis at a high concentration as well. After treatment with aspirin, SW480 cells displayed typically morphological features of apoptosis and necrosis under TEM, and increased the Bcl-2 expression in cells, but the expression of Bax was down regulated. CONCLUSION: Aspirin inhibits proliferation and induces apoptosis of SW480 cells. Its anti-tumor mechanism may arrest cell cycle and shift Bax/Bcl-2 balance in cells.