Sustained exposure to Helicobacter pylori induces immune tolerance by desensitizing TLR6.

Helicobacter pylori (H. pylori, Hp) has been designated a class I carcinogen and is closely associated with severe gastric diseases. During colonization in the gastric mucosa, H. pylori develops immune escape by inducing host immune tolerance. The gastric epithelium acts as the first line of defense against H. pylori, with Toll-like receptors (TLRs) in gastric epithelial cells being sensitive to H. pylori components and subsequently activating the innate immune system. However, the mechanism of immune tolerance induced by H. pylori through the TLR signalling pathway has not been fully elucidated. In this research, we detected the expression of TLRs and inflammatory cytokines in GES-1 cells upon sustained exposure to H. pylori or H. pylori lysate from 1 to 30 generations and in Mongolian gerbils infected with H. pylori for 5 to 90 weeks. We found that the levels of TLR6 and inflammatory cytokines first increased and then dropped during the course of H. pylori treatment in vitro and in vivo. The restoration of TLR6 potentiated the expression of IL-1ß and IL-8 in GES-1 cells, which recruited neutrophils and reduced the colonization of H. pylori in the gastric mucosa of gerbils. Mechanistically, we found that persistent infection with H. pylori reduces the sensitivity of TLR6 to bacterial components and regulates the expression of inflammatory cytokines in GES-1 cells through TLR6/JNK signaling. The TLR6 agonist obviously alleviated inflammation in vitro and in vivo. Promising results suggest that TLR6 may be a potential candidate immunotherapy drug for H. pylori infection.

Investigating the Molecular Mechanisms Underlying Early Response to Inflammation and Helicobacter pylori Infection in Human Gastric Epithelial Cells.

Helicobacter pylori is a leading cause of chronic gastric inflammation, generally associated with gastritis and adenocarcinoma. Activation of the NF-κB pathway mainly contributes to the inflammatory phenotype observed in H. pylori infection in humans and experimental models. Since the gastric epithelium undergoes rapid turnover, inflammation and pathogenicity of H. pylori result from early phase and chronically activated pathways. In the present study we investigated the early host response to H. pylori in non-tumoral human gastric epithelial cells (GES-1). To dissect the pathogen-specific mechanisms we also examined the response to tumor necrosis factor (TNF), a prototypical cytokine. By analyzing the activation state of NF-κB signaling, cytokine expression and secretion, and the transcriptome, we found that the inflammatory response of GES-1 cells to H. pylori and TNF results from activation of multiple pathways and transcription factors, e.g., NF-κB and CCAAT/enhancer-binding proteins (CEBPs). By comparing the transcriptomic profiles, we found that H. pylori infection induces a less potent inflammatory response than TNF but affects gene transcription to a greater extent by specifically inducing transcription factors such as CEBPß and numerous zinc finger proteins. Our study provides insights on the cellular pathways modulated by H. pylori in non-tumoral human gastric cells unveiling new potential targets.

Ovotransferrin Inhibits TNF-α Induced Inflammatory Response in Gastric Epithelial Cells via MAPK and NF-κB Pathway.

Ovotransferrin (OVT) has been confirmed to have anti-inflammatory activity. However, its effect and mechanism on gastric inflammation are unclear. In this study, the effect and mechanism of the OVT on the tumor necrosis factor-α (TNF-α) induced inflammatory response in gastric epithelial cells (GES-1) were investigated. The enzyme linked immunosorbent assay (ELISA) was used to determine the levels of inflammation cytokines, followed by RNA sequencing to explore the potential pathways of its anti-inflammatory effect, and then it was validated by Western blotting and pathways inhibitors. Results showed that the OVT at concentrations of 50-400 µg/mL displayed nontoxicity against GES-1 cells. Additionally, 100 µg/mL of OVT obviously reduced the secretion of interleukin (IL)-8, IL-6, and TNF-α by 63.02% (630.09/1703.98), 35.53% (935.81/1451.43), and 36.19% (964.60/1511.63), respectively. The results of RNA sequencing exhibited that the OVT significantly influences the activation of mitogen-activated protein kinase (MAPK) and the nuclear factor kappa-light-chain enhancer of activated B cell (NF-κB) pathways, which was verified by the levels of p-IKK, p-IκB, p-P65, p-ERK, p-JNK, and p-P38 protein. IL-8 contents released by GES-1 cells after incubation with inhibitors of NF-κB and MAPK pathways further confirmed that OVT hindered activation of these two pathways. Collectively, these results suggested that OVT was a natural protein with the potential to treat gastric inflammation.

Inhibitory effect of astragalus membranaceus injection on apoptosis and autophagy induced by enterovirus 71 / 中国生物制品学杂志

@#Objective To investigate the effect of astragalus membranaceus（AM）injection on apoptosis and autophagy of human gastric epithelial cell line（GES⁃1）induced by enterovirus 71（EV71）. Methods GES⁃1 cells were cultured in vitro and divided into infected group（EV71 infected at a MOI of 3 and control group（no virus infected）. The morpho⁃logical changes of EV71 infected cells were observed by inverted microscope. The level of VP1 in GES⁃1 cells infected with EV71 was detected by Western blot；CCK⁃8 assay was used to detect the viability of GES⁃1 cells infected with EV71；Nuclear staining with DAPI was used to observe the morphological changes of nuclear apoptosis infected with EV71. GES⁃1 cells were divided into control group（without virus infection），infection group and AM intervention group with final concentration of 1，2. 5，5 and 10 μg／mL，respectively. Western blot was used to detect the effect of AM intervention on the expression of apoptosis⁃related proteins Caspase⁃3，PARP and autophagy⁃related proteins LC3 and P62 in GES⁃1 cells infected withEV71. CCK⁃8 method was used to detect the effect of AM intervention on the viability of GES⁃1 cells infected with EV71. Results GES⁃1 cells were round，shrunken with nuclear pyknosis and uneven size；VP1 level increased（t = 41. 56，P < 0. 01），cell viability decreased（t = 19. 07，P < 0. 01），Caspase⁃3 and PARP proteins were cut off（t = 35. 29 and 3. 648， P < 0. 01 and 0. 021 8，respectively），LC3Ⅱ／LC3Ⅰ ratio increased（t = 10. 16，P = 0. 000 5）and P62 protein was degraded（t = 68. 68，P < 0. 01）；AM inhibited the degradation of Caspase⁃3，PARP and P62 proteins induced by EV71 （t = 52. 66，59. 60 and 40. 22，respectively，each P < 0. 01）and increased the ratio of LC3Ⅱ／LC3Ⅰ（t = 5. 521，P = 0. 005 3），andreducedtheinhibitoryeffectofEV71ontheviabilityofGES⁃1cells（t =4. 420，P =0. 0115）. Conclusion EV71 infection induced apoptosis of GES⁃ 1 cells and AM intervention inhibited EV71 induced apoptosis by inhibiting EV71 induced autophagy.

Protective Effects of Piperine on Ethanol-Induced Gastric Mucosa Injury by Oxidative Stress Inhibition.

Piper nigrum Linnaeus is often used as a treatment for chills, stomach diseases, and other ailments. Piperine has many biological functions; however, its mechanism for preventing gastric mucosal damage is still unclear. The objective of this study was to investigate the preventive effects of piperine on ethanol-induced gastric mucosal injury by using GES-1 cells and rats. SOD, CAT, GSH-Px and MDA were effectively regulated in GES-1 cells pre-treated with piperine. Piperine significantly increased SOD, CAT and GSH-Px activities, but decreased the ulcer area, MDA, ROS and MPO levels in the gastric tissues of rats. RT-PCR analysis showed that piperine downregulated the mRNA expression levels of keap1, JNK, ERK and p38, and upregulated the mRNA transcription levels of Nrf2 and HO-1. Western blotting results indicated that piperine could activate the protein expression levels of Nrf2 and HO-1 and inhibit the protein expression levels of keap1, p-JNK, p-ERK and p-p38. In conclusion, piperine suppressed ethanol-induced gastric ulcers in vitro and in vivo via oxidation inhibition and improving gastric-protecting activity by regulating the Nrf2/HO-1 and MAPK signalling pathways.

Vacuolating Cytotoxin A Triggers Mitophagy in Helicobacter pylori-Infected Human Gastric Epithelium Cells.

Helicobacter pylori (H. pylori)-derived vacuolating cytotoxin A (VacA) causes damage to various organelles, including mitochondria, and induces autophagy and cell death. However, it is unknown whether VacA-induced mitochondrial damage can develop into mitophagy. In this study, we found that H. pylori, H. pylori culture filtrate (HPCF), and VacA could activate autophagy in a gastric epithelial cell line (GES-1). VacA-caused mitochondrial depolarization retards the import of PINK1 into the damaged mitochondria and evokes mitophagy. And, among mass spectrometry (LC-MS/MS) identified 25 mitochondrial proteins bound with VacA, Tom20, Tom40, and Tom70, TOM complexes responsible for PINK1 import, were further identified as having the ability to bind VacA in vitro using pull-down assay, co-immunoprecipitation, and protein-protein docking. Additionally, we found that the cell membrane protein STOM and the mitochondrial inner membrane protein PGAM5 also interacted with VacA. These findings suggest that VacA captured by STOM forms endosomes to enter cells and target mitochondria. Then, VacA is transported into the mitochondrial membrane space through the TOM complexes, and PGAM5 aids in inserting VacA into the inner mitochondrial membrane to destroy the membrane potential, which promotes PINK1 accumulation and Parkin recruitment to induce mitophagy. This study helps us understand VacA entering mitochondria to induce the mitophagy process.

5-Hydroxymethylfurfural Exerts Negative Effects on Gastric Mucosal Epithelial Cells by Inducing Oxidative Stress, Apoptosis, and Tight Junction Disruption.

5-Hydroxymethylfurfural (5-HMF) is a processing byproduct present in foods that are consumed daily by humans, and the diet is the principal route for human exposure to it. However, its adverse effects on gastric epithelial cells are not fully understood. Based on the half inhibitory concentration value, concentrations of HMF of 2, 4, 8, and 16 mM were selected for this study. After 5-HMF treatment for 24 h, the number of living cells decreased to 89.61 ± 0.48, 77.30 ± 0.57, 58.75 ± 0.36, and 19.61 ± 0.40% of the control, respectively. Apoptosis activated through both the death receptor and mitochondrial pathways was confirmed to be the primary mode of HMF-induced cell death. Further analysis revealed that the reactive oxygen species (ROS) levels in GES-1 cells increased 1.7-6.5 fold after exposure to 5-HMF. Moreover, the inhibition of ROS by N-acetylcysteine blocked HMF-induced apoptosis and cell proliferation suppression, indicating that oxidative stress was important in HMF-induced apoptosis. Besides, after 5-HMF treatment, the gene expressions of occludin and ZO-1 were reduced by 1.1-3.4 fold and 2.0-9.4 fold, respectively. The cell surface morphology and tight junction-related protein expression analysis also revealed the destructive effect of 5-HMF on tight junction integrity. Our research highlights a potential mechanism of HMF-induced toxicity in GES-1 cells and provides additional information on the health risks of 5-HMF exposure to the human gastric epithelium.

4'-O-methylpyridoxine: Preparation from Ginkgo biloba Seeds and Cytotoxicity in GES-1 Cells.

Ginkgo biloba seeds are wildly used in the food and medicine industry. It has been found that 4'-O-methylpyridoxine (MPN) is responsible for the poisoning caused by G. biloba seeds. The objective of this study was to explore and optimize the extraction method of MPN from G. biloba seeds, and investigate its toxic effect on human gastric epithelial cells (GES-1) and the potential related mechanisms. The results showed that the extraction amount of MPN was 1.933 µg/mg, when extracted at 40 °C for 100 min, with the solid-liquid ratio at 1:10. MPN inhibited the proliferation of GES-1 cells, for which the inhibition rate was 38.27% when the concentration of MPN was 100 µM, and the IC50 value was 127.80 µM; meanwhile, the cell cycle was arrested in G2 phase. High concentration of MPN (100 µM) had significant effects on the nucleus of GES-1 cells, and the proportion of apoptotic cells reached 43.80%. Furthermore, the Western blotting analysis showed that MPN could reduce mitochondrial membrane potential by increasing the expression levels of apoptotic proteins Caspase 8 and Bax in GES-1 cells. In conclusion, MPN may induce apoptosis in GES-1 cells, which leads to toxicity in the human body.

Protective effect of against ethanol-induced gastric ulcer and its mechanism.

: To investigate the protective effect of (FD) against ethanol-induced gastric ulcer and its mechanism. : Human gastric epithelial GES-1 cells were divided into normal control group, model control group, FD 95% alcohol extract group, FD 50% alcohol extract group and FD decoction extract group. Gastric ulcer was induced by treatment with 1% ethanol in GES-1 cells. The cell proliferation was detected with MTT method in each group. Sixty SD rats were randomly divided into normal control group, model control group, ranitidine group and low-dose, medium-dose, high-dose FD 95% alcohol extract groups (150, 300, 600 mg/kg). The corresponding drugs were administrated by gavage for The gastric ulcer model was induced by intragastric administration of anhydrous ethanol. The gastric ulcer area and ulcer inhibition rate of rats were measured in each group; the degree of gastricmucosal damage was observed by scanning electron microscopy; the levels of tumor necrosis factor (TNF)-α, interleukin (IL)-6, IL-1ß in serum and the content of malondialdehyde (MDA), superoxide dismutase (SOD), glutathione (GSH), catalase (CAT) in gastric tissues were detected by ELISA method. : 95% alcohol extract of FD had the strongest protective effect on proliferation of GES-1 cells. In animal experiments, compared with the normal control group, a large area of ulcers appeared on the gastric mucosa in the model control group, while the ulcer areas of the FD groups and ranitidine group were significantly smaller than that of the model control group (all <0.05). Compared with the model control group, FD groups and ranitidine group significantly reduced the levels of TNF-α, IL-1ß, IL-6 in serum and the MDA content in the gastric tissues, and increased the activity of SOD, CAT and GSH in gastric tissues (all <0.05). : The 95% alcohol extract of FD can reduce the levels of TNF-α, IL-1ß and IL-6 in serum and the content of MDA in gastric tissues, and increase the activity of SOD, CAT and GSH in gastric tissues to achieve the protective effect against gastric ulcer.

The mechanism of miR-363-3p/DUSP10 signaling pathway involved in the gastric mucosal injury induced by clopidogrel.

Clopidogrel-induced gastric injury is an important clinical problem. However, the exact mechanism is still unclarified. Increasing evidence indicates that miRNAs may be involved in the pathogenesis of gastric mucosal injury. In this study, the aim was to investigate the role of miR-363-3p in the gastric mucosal injury caused by clopidogrel. MiRNA microarray analysis was performed using paired gastric mucosal in order to find differential expression of miRNAs. The levels of miR-363-3p were examined in gastric mucosal injury caused by clopidogrel. The GES-1 cells were used as a model system, miR-363-3p mimic/inhibitor was transfected into GES-1 cells, then GES-1 cells were treated with clopidogrel. The levels of miR-363-3p and DUSP10 were examined in GES-1 cells using quantitative real-time PCR (qRT-PCR). CCK-8 assay and flow cytometry analysis were used to detect cell proliferation and apoptosis, respectively. Western blot assay was used to measure the protein levels of DUSP10. The interaction between miR-363-3p and DUSP10 was determined by luciferase reporter assay. MiR-363-3p was selected as a differentially expressed miRNA. The expression of miR-363-3p in gastric mucosal injury caused by clopidogrel was higher than that in normal samples. Also, depletion of miR-363-3p increased the proliferation of GES-1 cells and reduced the apoptosis. Luciferase-reporting assay results confirmed that DUSP10 was one of the target genes of miR-363-3p. DUSP10 inhibited apoptosis in GES-1 cells treated by clopidogrel. Moreover, DUSP10 knockdown abrogated the inhibitory effects on apoptosis in GES-1 cells mediated by miR-363-3p inhibitor. Knockdown of miR-363-3p increased the proliferation and reduced the apoptosis by targeting DUSP10 in GES-1 cells treated by clopidogrel, indicating that miR-363-3p may be a potential therapeutic target for gastric mucosal injury caused by clopidogrel.

Protective effect of against ethanol-induced gastric ulcer and its mechanism / 浙江大学学报·医学版

: To investigate the protective effect of (FD) against ethanol-induced gastric ulcer and its mechanism. : Human gastric epithelial GES-1 cells were divided into normal control group, model control group, FD 95% alcohol extract group, FD 50% alcohol extract group and FD decoction extract group. Gastric ulcer was induced by treatment with 1% ethanol in GES-1 cells. The cell proliferation was detected with MTT method in each group. Sixty SD rats were randomly divided into normal control group, model control group, ranitidine group and low-dose, medium-dose, high-dose FD 95% alcohol extract groups (150, 300, 600 mg/kg). The corresponding drugs were administrated by gavage for The gastric ulcer model was induced by intragastric administration of anhydrous ethanol. The gastric ulcer area and ulcer inhibition rate of rats were measured in each group; the degree of gastricmucosal damage was observed by scanning electron microscopy; the levels of tumor necrosis factor (TNF)-α, interleukin (IL)-6, IL-1β in serum and the content of malondialdehyde (MDA), superoxide dismutase (SOD), glutathione (GSH), catalase (CAT) in gastric tissues were detected by ELISA method. : 95% alcohol extract of FD had the strongest protective effect on proliferation of GES-1 cells. In animal experiments, compared with the normal control group, a large area of ulcers appeared on the gastric mucosa in the model control group, while the ulcer areas of the FD groups and ranitidine group were significantly smaller than that of the model control group (all <0.05). Compared with the model control group, FD groups and ranitidine group significantly reduced the levels of TNF-α, IL-1β, IL-6 in serum and the MDA content in the gastric tissues, and increased the activity of SOD, CAT and GSH in gastric tissues (all <0.05). : The 95% alcohol extract of FD can reduce the levels of TNF-α, IL-1β and IL-6 in serum and the content of MDA in gastric tissues, and increase the activity of SOD, CAT and GSH in gastric tissues to achieve the protective effect against gastric ulcer.

Antioxidant activity and absorption of cyanidin-3-O-glucoside liposomes in GES-1 cells in vitro.

The use of anthocyanins are limited by their chemical properties. Recent evidence suggests Cyanidin-3-O-glucoside (C3 G) liposomes via the ethanol injection method exhibit improved stability. In the current study, the characterization and cell absorption of C3 G liposomes were explored via transmission electron microscopy and flow cytometry. The internalization of the C3 G liposomes across the gastric epithelial cell monolayer (GES-1 cells) were investigated. Results showed that the particle size and encapsulation efficiency were 234 ± 9.35 nm and 75.0% ± 0.001, respectively. The total antioxidant capacity (T-AOC) and malondialdehyde (MDA) content were used to evaluate the antioxidant activity of C3 G liposomes. The C3 G liposomes can obviously increased T-AOC and decreased the MDA content.Collectively, C3 G liposomes protected human GES-1 cells from gastric mucosal injury induced by H2O2 by activating the related antioxidant pathway. Our research could provide a new effective treatment strategy for the absorption of stomach drugs.Abbreviations: C3G: Cyanidin-3-O-glucoside; LP: Liposome; GES-1 cells: Human gastric epithelial cell lines; FBS: Fetal Bovine Serum; PBS: Phosphate-buffered saline; PC: Phosphatidylcholine; CH: Cholesterol; MDA: Malondialdehyde; TEM: Transmission electron microscope; FCM: Flow cytometry; FITC: Fluorescein isothiocyanate; DAPI: 4', 6-diamidino-2phenylidole; FT-IR: Fourier Transform infrared spectroscopy; PFA: Paraformaldehyde.

Involvement of PERK-CHOP pathway in fumonisin B1- induced cytotoxicity in human gastric epithelial cells.

Fumonisin B1 (FB1) is a mycotoxin, produced by Fusarium verticillioides and Fusarium proliferatum, and a common fungal contaminant of maize worldwide. Its potential health hazard as a natural toxin is well documented in human and domestic animals. However, the molecular mechanism and the key factors responsible for FB1-induced cytotoxicity have not been elucidated. In this study, we first examined the cytotoxicity induced by FB1 in human gastric epithelial cell line (GES-1). We found that FB1 notably decreased cell viability and induced apoptotic cell death. Furthermore, the levels of ER stress markers were significantly increased after FB1 exposure and the ER stress inhibitor 4-phenylbutyric acid strongly suppressed FB1-induced cytotoxicity. Interestingly, the inhibition of PERK activity by GSK2606414 or shPERK3 blocked FB1-induced apoptotic cell death and cell proliferation suppression, which indicated that the cytotoxicity induced by FB1 was dependent on this signalling pathway. Moreover, myriocin could relieve FB1-induced ER stress and prevent cell death, which implied that the disruption of sphingolipid metabolism is an apical event for FB1-induced cytotoxicity. In the present study, we demonstrated that the ER stress-related PERK-CHOP signalling pathway is a novel mechanism for FB1-induced cytotoxicity and the gastrointestinal injury caused by FB1 should be concerned in the future.

A novel Hericium erinaceus polysaccharide: Structural characterization and prevention of H2O2-induced oxidative damage in GES-1 cells.

In this paper, the structural characteristics and bioactivity of a novel polysaccharide from H. erinaceus (HEPN) were investigated, wherein, physico-chemical characterization demonstrated that HEPN with an average molecular weight of 12.713 kDa was composed of mannose (5.13%), glucose (43.02%), and galactose (51.85%). The models in vitro for preventing oxidative damage of human gastric epithelium (GES-1) cells were established and used to investigate the preventive effects of HEPN from oxidative damage. It was found that HEPN could significantly prevent GES-1 cells against H2O2-induced oxidative damage by promoting cell proliferation, inhibiting cell necrosis, reducing ROS levels, regulating mitochondrial membrane potential and maintaining mitochondrial membrane permeability. These results indicated HEPN can effectively prevent gastric cell damage in vitro and suggested the potential application of HEPN as bioactive ingredient for healthy foods.

Cyanidin-3-o-glucoside liposome: Preparation via a green method and antioxidant activity in GES-1 cells.

Cyanidin-3-O-glucoside (C3G) liposomes was used to improve the stability and antioxidant activity of C3G through a green thin-film dispersion method. The characteristics, stability and the effect of C3G liposomes on GES-1 cells were explored. Results showed that the particle size and encapsulation efficiency (EE%) of C3G liposomes were 258.9 ±â€¯5.06 nm and 77.5%, respectively. DPPH assay showed that liposomes encapsulation can improve the antioxidant of C3G, while the ABTS assay was opposite. Stability study showed the C3G liposome were unstable under extended storage time. The effects of C3G liposomes on GES-1 cells showed that C3G liposomes can decrease the ROS levels of GES-1 and had negligible effects on cell viability and mitochondrial structure. These findings suggested that liposomes could be used as a carrier system to improve the stability of C3G.

Upregulation of TMEFF2 is involved in the antiproliferative effects of vitamin C and tyrphostin AG490 on GES-1 and AGS cells.

Transmembrane protein with epidermal growth factor (EGF)-like and two follistatin motifs 2 (TMEFF2) is downregulated in human gastric cancer, and its levels are associated with tumor aggressiveness. Herein, a positive correlation was identified between serum vitamin C levels (µg/ml) and mRNA levels of TMEFF2 in gastric cancer tissue. TMEFF2 silencing promotes cell proliferation in GES-1 normal human gastric epithelial cells and AGS human gastric adenocarcinoma cells. Notably, vitamin C and AG490 exerted antiproliferative effects on the two cell lines. The present study demonstrated that small interfering (si)-RNA-TMEFF2 exerts pro-proliferative effects on GES-1 and AGS cells. The results revealed that vitamin C significantly inhibited the growth of GES-1 and AGS cells by reducing cell viability, decreasing the expression of proliferating cell nuclear antigen (PCNA), and blocking the STAT3 pathway. Moreover, siRNA-TMEFF2-induced enhanced cell viability and PCNA expression were significantly reversed by additional vitamin C treatment; notably, markedly enhanced TMEFF2 expression was observed. Upregulated TMEFF2 expression was observed in association with the antiproliferative effect of AG490. In conclusion, serum vitamin C content (µg/ml) was positively correlated with the mRNA levels of TMEFF2 in gastric cancer tissue. Exploring novel drugs that target TMEFF2 is a potential therapeutic strategy for blocking human GC.

Effects of TIN2 on telomeres and chromosomes in the human gastric epithelial cell line GES-1.

TERF1-interacting nuclear factor 2 (TIN2) is a key member of the protein complexes that protect telomeres. TIN2 contributes an important role in biological processes. In a previous study by the present authors, an association was reported between high TIN2 protein expression and gastric cancer. Therefore, it was hypothesized that abnormal TIN2 expression may cause the development of malignancies, including, gastric carcinomas. To investigate this hypothesis, the present study employed peptide nucleic acid fluorescence in situ hybridization technology to analyze the human gastric epithelial GES-1 cells with high TIN2 expression or inhibited TIN2 expression. The results indicated that GES-1 cell lines with high TIN2 expression exhibited greater telomere dysfunction-induced damage compared with GES-1 cell lines with inhibited TIN2 expression. Chromosome analysis indicated that GES-1 cells with high TIN2 expression exhibited 2.48±1.30 aberrant chromosomal changes per 100 cells, that may contribute to telomere DNA damage. Therefore, aberrant chromosomal alterations may provide a novel perspective for the pathogenesis of gastric cancer.

Inconsistent effect of chloroquine on apoptosis of normal gastric epithelial cells GES-1 and gastric cancer cell line HGC-27 / 中国免疫学杂志

Objective:To compare the effect of chloroquine on apoptosis of normal gastric epithelial cells and gastric cancer cell line HGC-27. Methods:Change of these two kinds of cells were observed by inverted microscope after treating with CQ. HGC-27 cells were detected on the effect of apoptosis by DAPI nuclear staining after treating with CQ. The proliferation of cells were measured by CCK-8. Changes of mitochondrial membrane potential were investigated by JC-1 after treating with CQ. The expression of apoptosis protein effector enzyme Caspase-3 and substrate PARP in these two kinds of cells were tested by Western blot after using chloroquine (CQ) and rapamycin ( rapamycin, RAP ) to treat cells 72 h. Results: After treated with 10 μmol/L CQ 72 h, morphological characteristics of GES-1 cells and HGC-27 cells could be visible under the microscope,CQ induced apoptosis of GES-1 cells,on the contrary,it could make the HGC-27 cell get widened,the number of apoptotic cells gradually increased,the cell density decreased,cell atrophy and gradually turned round,cytoplasm reduced,at last,lose normal cell morphology. After two kinds of cells treated with CQ 72 h,as for GES-1 cell nuclei stained light,nuclear size and shape were not changed,however,HGC-27 nuclei showed pyknosis or granular fluorescence dense concentrated form. CCK-8 results showed that comparing with normal gastric epithelial cells GES-1,the pro-liferation of gastric cancer HGC-27 cells activity could be inhibited by CQ. JC-1 results showed that the change of the red fluorescence to green fluorescence in HGC-27 cells treated by CQ. Western blot showed that after being treated with CQ and RAP in normal gastric epithelial cells and HGC-27 cell line 72 h,the expression of apoptosis protein Caspase-3 and PARP in gastric cancer cell HGC-27 decreased significantly,comparing to that in GES-1 cells. Conclusion:Compared to normal gastric epithelial cells,CQ can inhibit human gastric cancer HGC-27 cell viability and induce apoptosis.

KH-type splicing regulatory protein mediate inflammatory response in gastric epithelial cells induced by lipopolysaccharide.

To study differential expressions of KH-type splicing regulatory protein (KSRP) and inflammatory factors and to explore the relationship between them in Lipopolysaccharide (LPS)-induced gastric epithelial cells (GES-1), cells were exposed to LPS for 24 h in the presence or absence of SC-514. Western blot and real-time PCR (RT-PCR) were used to analysis the contents of KSRP, inducible NO synthase (iNOS) and cyclooxygenase-2 (COX-2). The results showed that LPS decreased the expression of KSRP protein in GES-1 cells, but not KSRP mRNA, while increasing the levels of iNOS and COX-2 proteins and mRNAs in GES-1cells. High expression of KSRP induced low expressions and stabilities of iNOS and COX-2 in GES-1 cells, indicated that KSRP protein presented negative correlation with iNOS and COX-2 with LPS stimulation. In conclusion, the regulation of expression of KSRP was mainly achieved through post-translational modification. KSRP protein participated in regulating the expression of iNOS and COX-2 in their transcription and translation levels. In response to LPS or gram negative pathogenic microorganism, KSRP could regulate Toll-like receptor (TLR)/ Nuclear factor-kappa B (NF-κB) signal pathway in GES-1 cells.

Preconditioning of ulinastatin alleviates GES-1 cell injury induced by oxygen and glucose deprivation / 实用医学杂志

Objective To observe the effects of the preconditioning of ulinastatin on GES-1 cell injury induced by oxygen and glucose deprivation (OGD). Methods GES-1 cells were cultured in vitro and divided into three groups: normal control group (group N), oxygen and glucose deprivation group (group O), and ulinastatin preconditioning group (group U). The OGD model of GES-1 cells were established by glucose-free medium and three-gas incubator for 6h. Ulinastatin was added to group U 12h before the deprivation of oxygen and glucose. The cell viability and apoptosis were determined by cck-8 and flow cytometry respectively. Western Blot was used to examine the protein expression of Caspase-3 and Cleaved Caspase-3. The TRPV1 mRNA expression was measured by quantitative real-time PCR. Results As compared with group N, the viability of GES-1 was decreased, the apoptotic rate and the expression of Caspase-3 and Cleaved Caspase-3 were increased, and the TRPV1 mRNA expression decreased greatly in group O (P < 0.05). As compared with group O, the aforementioned changes were significantly inhibited in group U. Conclusions Ulinastatin preconditioning could effectively inhibit GES-1 cell injury induced by OGD, which may be related to the inhibition of apoptosis and the upregulation of TRPV1 mRNA expression.