circRNA3669 promotes goat endometrial epithelial cells proliferation via miR-26a/RCN2 to activate PI3K/AKT-mTOR and MAPK pathways

The development of receptive endometrium(RE) from pre-receptive endometrium(PE) for successful embryo implantation is a complex dynamic process in which the morphology and physiological states of the endometrial epithelium undergo a series of significant changes, including cell proliferation and apoptosis. However, the molecular mechanisms are not yet fully understood. In this study, a higher circRNA3669 level was observed in PE than in RE of goats. Functional assays revealed that this overexpression promoted the proliferation of goat endometrial epithelial cells(GEECs) by activating the expression of genes related to the PI3K/AKT-mTOR and MAPK pathways,thereby inhibiting apoptosis in vitro. Furthermore, circRNA3669 functioned as a competing endogenous RNA(ceRNA) to upregulate Reticulocalbin-2(RCN2) expression at the post-transcriptional level by interacting with and downregulating miR-26a in GEECs. In addition, RCN2, which is highly expressed in the PE of goats, was found to be regulated by β-estradiol(E2) and progesterone(P4). Our results demonstrated that RCN2 also affected the key proteins PI3K, AKT, mTOR, JNK, and P38 in the PI3K/AKT-mTOR and MAPK pathways, thereby facilitating GEECs proliferation and suppressing their apoptosis in vitro. Collectively, we constructed a new circRNA3669-miR-26aRCN2 regulatory network in GEECs, which further provides strong evidence that circRNA could potentially play a crucial regulatory role in the development of RE in goats.

SIRT1 inhibits apoptosis of human lens epithelial cells through suppressing endoplasmic reticulum stress in vitro and in vivo

AIM:To explore the effect of silent information regulator factor 2-related enzyme 1(SIRT1)on modulating apoptosis of human lens epithelial cells(HLECs)and alleviating lens opacification of rats through suppressing endoplasmic reticulum(ER)stress.METHODS:HLECs(SRA01/04)were treated with varying concentrations of tunicamycin(TM)for 24h,and the expression of SIRT1 and C/EBP homologous protein(CHOP)was assessed using real-time quantitative polymerase chain reaction(RT-PCR),Western blotting,and immunofluorescence.Cell morphology and proliferation was evaluated using an inverted microscope and cell counting kit-8(CCK-8)assay,respectively.In the SRA01/04 cell apoptosis model,which underwent siRNA transfection for SIRT1 knockdown and SRT1720 treatment for its activation,the expression levels of SIRT1,CHOP,glucose regulated protein 78(GRP78),and activating transcription factor 4(ATF4)were examined.The potential reversal of SIRT1 knockdown effects by 4-phenyl butyric acid(4-PBA;an ER stress inhibitor)was investigated.In vivo,age-related cataract(ARC)rat models were induced by sodium selenite injection,and the protective role of SIRT1,activated by SRT1720 intraperitoneal injections,was evaluated through morphology observation,hematoxylin and eosin(H&E)staining,Western blotting,and RT-PCR.RESULTS:SIRT1 expression was downregulated in TMinduced SRA01/04 cells.Besides,in SRA01/04 cells,both cell apoptosis and CHOP expression increased with the rising doses of TM.ER stress was stimulated by TM,as evidenced by the increased GRP78 and ATF4 in the SRA01/04 cell apoptosis model.Inhibition of SIRT1 by siRNA knockdown increased ER stress activation,whereas SRT1720 treatment had opposite results.4-PBA partly reverse the adverse effect of SIRT1 knockdown on apoptosis.In vivo,SRT1720 attenuated the lens opacification and weakened the ER stress activation in ARC rat models.CONCLUSION:SIRT1 plays a protective role against TM-induced apoptosis in HLECs and slows the progression of cataract in rats by inhibiting ER stress.These findings suggest a novel strategy for cataract treatment focused on targeting ER stress,highlighting the therapeutic potential of SIRT1 modulation in ARC development.

Overexpression of TRPV1 activates autophagy in human lens epithelial cells under hyperosmotic stress through Ca^(2+)-dependent AMPK/mTOR pathway

●AIM:To explore whether autophagy functions as a cellular adaptation mechanism in lens epithelial cells(LECs)under hyperosmotic stress.●METHODS:LECs were treated with hyperosmotic stress at the concentration of 270,300,400,500,or 600 mOsm for 6,12,18,24h in vitro.Polymerase chain reaction(PCR)was employed for the mRNA expression of autophagyrelated genes,while Western blotting detected the targeted protein expression.The transfection of stub-RFP-sens-GFPLC3 autophagy-related double fluorescence lentivirus was conducted to detect the level of autophagy flux.Scanning electron microscopy was used to detect the existence of autolysosome.Short interfering RNA of autophagy-related gene(ATG)7,transient receptor potential vanilloid(TRPV)1 overexpression plasmid,related agonists and inhibitors were employed to their influence on autophagy related pathway.Flow cytometry was employed to test the apoptosis and intracellular Ca^(2+)level.Mitochondrial membrane potential was measured by JC-1 staining.The cell counting kit-8 assay was used to calculate the cellular viability.The wound healing assay was used to evaluate the wound closure rate.GraphPad 6.0 software was utilized to evaluate the data.●RESULTS:The hyperosmotic stress activated autophagy in a pressure-and time-dependent manner in LECs.Beclin 1 protein expression and conversion of LC3B II to LC3B I increased,whereas sequestosome-1(SQSTM1)protein expression decreased.Transient Ca^(2+)influx was stimulated caused by hyperosmotic stress,levels of mammalian target of rapamycin(mTOR)phosphorylation decreased,and the level of AMP-activated protein kinase(AMPK)phosphorylation increased in the early stage.Based on this evidence,autophagy activation through the Ca^(2+)-dependent AMPK/mTOR pathway might represent an adaptation process in LECs under hyperosmotic stress.Hyperosmotic stress decreased cellular viability and accelerated apoptosis in LECs and cellular migration decreased.Inhibition of autophagy by ATG7 knockdown had similar results.TRPV1 overexpression increased autophagy and might be crucial in the occurrence of autophagy promoted by hyperosmotic stress.●CONCLUSION:A combination of hyperosmotic stress and autophagy inhibition may be a promising approach to decrease the number of LECs in the capsular bag and pave the way for improving prevention of posterior capsular opacification and capsular fibrosis.

Umbilical cord mesenchymal stem cell exosomes alleviate necrotizing enterocolitis in neonatal mice by regulating intestinal epithelial cells autophagy

BACKGROUND Necrotizing enterocolitis(NEC)is a severe gastrointestinal disease that affects premature infants.Although mounting evidence supports the therapeutic effect of exosomes on NEC,the underlying mechanisms remain unclear.AIM To investigate the mechanisms underlying the regulation of inflammatory response and intestinal barrier function by umbilical cord mesenchymal stem cell(UCMSCs)exosomes,as well as their potential in alleviating NEC in neonatal mice.METHODS NEC was induced in 5-d-old C57BL/6 pups through hypoxia and gavage feeding of formula containing lipopolysaccharide(LPS),after which the mice received human UCMSC exosomes(hUCMSC-exos).The control mice were allowed to breastfeed with their dams.Ileal tissues were collected from the mice and analyzed by histopathology and immunoblotting.Colon tissues were collected from NEC neonates and analyzed by immunofluorescence.Molecular biology and cell culture approaches were employed to study the related mechanisms in intestinal epithelial cells.RESULTS We found that autophagy is overactivated in intestinal epithelial cells during NEC,resulting in reduced expression of tight junction proteins and an increased inflammatory response.The ability of hUCMSC-exos to ameliorate NEC in a mouse model was dependent on decreased intestinal autophagy.We also showed that hUCMSC-exos alleviate the inflammatory response and increase migration ability in intestinal epithelial cells induced by LPS.CONCLUSION These results contribute to a better understanding of the protective mechanisms of hUCMSC-exos against NEC and provide a new theoretical and experimental foundation for NEC treatment.These findings also enhance our understanding of the role of the autophagy mechanism in NEC,offering potential avenues for identifying new therapeutic targets.

Sulforaphane prevents LPS‑induced inflammation by regulating the Nrf2‑mediated autophagy pathway in goat mammary epithelial cells and a mouse model of mastitis

Background Mastitis not only deteriorates the composition or quality of milk,but also damages the health and pro-ductivity of dairy goats.Sulforaphane(SFN)is a phytochemical isothiocyanate compound with various pharmacologi-cal effects such as anti-oxidant and anti-inflammatory.However,the effect of SFN on mastitis has yet to be elucidated.This study aimed to explore the anti-oxidant and anti-inflammatory effects and potential molecular mechanisms of SFN in lipopolysaccharide(LPS)-induced primary goat mammary epithelial cells(GMECs)and a mouse model of mastitis.Results In vitro,SFN downregulated the mRNA expression of inflammatory factors(tumor necrosis factor-α(TNF-α),interleukin(IL)-1βand IL-6),inhibited the protein expression of inflammatory mediators(cyclooxygenase-2(COX2),and inducible nitric oxide synthase(iNOS))while suppressing nuclear factor kappa-B(NF-κB)activation in LPS-induced GMECs.Additionally,SFN exhibited an antioxidant effect by increasing Nrf2 expression and nuclear translocation,up-regulating antioxidant enzymes expression,and decreasing LPS-induced reactive oxygen species(ROS)produc-tion in GMECs.Furthermore,SFN pretreatment promoted the autophagy pathway,which was dependent on the increased Nrf2 level,and contributed significantly to the improved LPS-induced oxidative stress and inflammatory response.In vivo,SFN effectively alleviated histopathological lesions,suppressed the expression of inflammatory factors,enhanced immunohistochemistry staining of Nrf2,and amplified of LC3 puncta LPS-induced mastitis in mice.Mechanically,the in vitro and in vivo study showed that the anti-inflammatory and anti-oxidative stress effects of SFN were mediated by the Nrf2-mediated autophagy pathway in GMECs and a mouse model of mastitis.Conclusions These results indicate that the natural compound SFN has a preventive effect on LPS-induced inflam-mation through by regulating the Nrf2-mediated autophagy pathway in primary goat mammary epithelial cells and a mouse model of mastitis,which may improve prevention strategies for mastitis in dairy goats.

Tanshinone IIA protects intestinal epithelial cells from ferroptosis through the upregulation of GPX4 and SLC7A11

Background:Inflammatory bowel disease(IBD)is a chronic inflammatory disease of the gastrointestinal tract.The destruction of the intestinal epithelial barrier is one of the major pathological processes in IBD pathology.Growing evidence indicated that epithelial cell ferroptosis is linked to IBD and is considered a target process.Methods:RAS-selective lethal 3(RSL3)was used to induce ferroptosis in intestinal epithelial cell line No.6(IEC-6)cells,and cell ferroptosis and the effects of tanshinone IIA(Tan IIA)were determined by cell counting kit-8(CCK-8),reactive oxygen species(ROS)staining,Giemsa staining and transmission electron microscope(TEM).The cell viability of natural product library compounds was determined by CCK-8.The expression of ferroptosis-related genes were detected by real-time quantitative polymerase chain reaction(RT-qPCR)and western blot.Results:Treatment of IEC-6 cells results in the accumulation of ROS and typical morphological characteristics of ferroptosis.RSL3 treatment caused rapid cellular cytotoxicity which could be reversed by ferrostatin-1(Fer-1)in IEC-6 cells.Natural product library screening revealed that Tan IIA is a potent inhibitor of IEC-6 cell ferroptosis.Tan IIA could significantly protect the RSL3-induced ferroptosis of IEC-6 cells.Furthermore,the ferroptosis suppressors,glutathione peroxidase 4(GPX4),solute carrier family 7 member 11(SLC7A11),and miR-17-92 were found to be early response genes in RSL3-treated cells.Treatment of IEC-6 cells with Tan IIA resulted in upregulation of GPX4,SLC7A11,and miR-17-92.Conclusion:Our study demonstrated that Tan IIA protects IEC-6 cells from ferroptosis through the upregulation of GPX4,SLC7A11,and miR-17-92.The findings might provide a theoretical grounding for the future application of Tan IIA to treat or prevent IBD.

Role of reactive oxygen species in epithelial-mesenchymal transition and apoptosis of human lens epithelial cells

AIM:To investigate the role of reactive oxygen species(ROS)in epithelial–mesenchymal transition(EMT)and apoptosis of human lens epithelial cells(HLECs).METHODS:Flow cytometry was used to assess ROS production after transforming growth factorβ2(TGF-β2)induction.Apoptosis of HLECs after H_(2)O_(2) and TGF-β2 interference with or without ROS scavenger N-acetylcysteine(NAC)were assessed by flow cytometry.The corresponding protein expression levels of the EMT markerα-smooth muscle actin(α-SMA),the extracellular matrix(ECM),marker fibronectin(Fn),and apoptosis-associated proteins were detected by using Western blotting in the presence of an ROS scavenger(NAC).Wound-healing and Transwell assays were used to assess the migration capability of HLECs.RESULTS:TGF-β2 stimulates ROS production within 8h in HLECs.Additionally,TGF-β2 induced HLECs cell apoptosis,EMT/ECM synthesis protein markers expression,and pro-apoptotic proteins production;nonetheless,NAC treatment prevented these responses.Similarly,TGF-β2 promoted HLECs cell migration,whereas NAC inhibited cell migration.We further determined that although ROS initiated apoptosis,it only induced the accumulation of the EMT markerα-SMA protein,but not COL-1 or Fn.CONCLUSION:ROS contribute to TGF-β2-induced EMT/ECM synthesis and cell apoptosis of HLECs;however,ROS alone are not sufficient for EMT/ECM synthesis.

Morroniside ameliorates lipopolysaccharide-induced inflammatory damage in iris pigment epithelial cells through inhibition of TLR4/JAK2/STAT3 pathway

AIM:To investigate the effect of morroniside(Mor)on lipopolysaccharide(LPS)-treated iris pigment epithelial cells(IPE).METHODS:IPE cells were induced by LPS and treated with Mor.Cell proliferation was detected by cell counting kit(CCK)-8,apoptosis was detected by flow cytometry,the levels of tumor necrosis factor-α(TNF-α),interleukin(IL)-6,and IL-8 were measured by enzyme-linked immunosorbent assay(ELISA)kits,and the protein expression of TLR4,JAK2,p-JAK2,STAT3,and p-STAT3 was analyzed by Western blotting.In addition,overexpression of TLR4 and Mor treatment of LPS-stimulated IPE cells were also tested for the above indices.RESULTS:Mor effectively promoted the proliferation and inhibited the apoptosis of LPS-treated IPE cells.In addition,Mor significantly reduced the levels of TNF-α,IL-6,and IL-8 and significantly inhibited the expression of TLR4,p-JAK2,and p-STAT3 in LPS-treated IPE cells.The effect of Mor on LPS-treated IPE cells was markedly attenuated after overexpression of TLR4.CONCLUSION:These findings suggest that Mor may ameliorate LPS-induced inflammatory damage and apoptosis in IPE through inhibition of TLR4/JAK2/STAT3 pathway.

Primary Culture of Bovine Mammary Epithelial Cells

[ Objective] To investigate the feasibility of the primary culture of bovine mammary epithelial cells in biochemical incubator. [ Method] In vitro, bovine mammary epithelial cells were isolated and cultured by the tissue explant method in order to investigate the optimal culture conditions. The morphology observation and identification of the cultured cells were performed by inverted microscope observation, Giemsa staining and cytokeratin immunohistochemistry. [ Result] Observed with inverted microscope, most of the bovine mammary epithelial cells were polygonal and displayed typical slabstone-like appearance. As it can be seen from cell staining results, the cell body was big and the nucleus was stained dark blue and was round or oval in shape, with clearly visible nucleoli, generally 2 -4 nucleoli. The tissue-specific expression of cytokeratin 14 and cytokeratin 18 genes in mammary epithelial cells was identified by cytokeratin immunohistochemistry. [ Conclusion] Primary bovine mammary epithelial cells were successfully cultured in biochemical incubator.

Protective Effect and Autophagy Mechanism of Lycium barbarum Polysaccharides on Retinal Pigment Epithelial Cells Under High-Glucose Conditions

Objective:To study the effects of Lycium barbarum polysaccharide(LBP)on the proliferation,apoptosis,and autophagy of retinal pigment epithelial(RPE)cells cultured under high-glucose conditions.Methods:The ARPE-19 cell line was randomly divided into a control group(normally cultured in Dulbecco's Modified Eagle Medium/Nutrient Mixture F-12[DMEM/F-12]medium),a high-glucose group(HG;50 mmol/L glucose added to DMEM/F-12 medium),and a HG+LBP group(incubated in DMEM/F-12 medium containing 1 mg/mL LBP for 24 h,and then treated with 50 mmol/L glucose for 24 h).Following Ad-mCherry-GFP-LC3B infection,cell proliferation,apoptosis,mammalian target of rapamy-cin(mTOR)expression,and autophagic flux were determined by Cell Counting Kit-8(CCK-8),AnnexinV-APC/7-AAD Apoptosis Detection Kit,Western blot,and laser confocal microscopy,respectively.Results:The proliferation rate of ARPE-19 cells in the HG group was significantly lower than that in the control group(P<0.05),while the proliferation rate of ARPE-19 cells in the HG+LBP group was significantly higher than that in the HG group(P<0.05).The apoptosis rate of ARPE-19 cells in the HG group was significantly higher than that in the control group(P<0.05),while the apoptosis rate of ARPE-19 cells in the HG+LBP group was significantly lower than that in the HG group(P<0.05).The relative expression of phosphorylated mTOR(p-mTOR)of ARPE-19 cells in the HG group was significantly lower than that in the control group(P<0.05),with enhanced autophagic flux;when compared with the HG group,the HG+LBP group had significantly higher expression of p-mTOR(P<0.05),with diminished autophagic flux.Conclusion:LBP has a protective effect on RPE cells with high glucose-induced injury,and its mechanism may be related to LBP inhibition of high glucose-induced abnormal autophagy.

Acellular porcine corneal matrix as a carrier scaffold for cultivating human corneal epithelial cells and fibroblasts in vitro

AIM：To investigate the feasibility of corneal anterior lamellar reconstruction with human corneal epithelial cells and fibroblasts,and an acellular porcine cornea matrix（APCM） in vitro.·METHODS：The scaffold was prepared from fresh porcine corneas which were treated with 0.5%sodium dodecyl sulfate（SDS）solution and the complete removal of corneal cells was confirmed by hematoxylin-eosin（HE）staining and 4’,6-diamidino-2-phenylindole（DAPI）staining.Human corneal fibroblasts and epithelial cells were cultured with leaching liquid extracted from APCM,and then cell proliferative ability was evaluated by MTT assay.To construct a human corneal anterior lamellar replacement,corneal fibroblasts were injected into the APCM and cultured for 3d,followed by culturing corneal epithelial cells on the stroma construction surface for another 10d.The corneal replacement was analyzed by HE staining,and immunofluorescence staining.·R ESULTS：Histological examination indicated that there were no cells in the APCM by HE staining,and DAPI staining did not detect any residual DNA.The leaching liquid from APCM had little influence on the proliferation ability of human corneal fibroblasts and epithelial cells.At 10d,a continuous 3 to 5 layers of human corneal epithelial cells covering the surface of the APCM was observed,and the injected corneal fibroblasts distributed within the scaffold.The phenotype of the construction was similar to normal human corneas,with high expression of cytokeratin 12 in the epithelial cell layer and high expression of Vimentin in the stroma.·CONCLUSION：Corneal anterior lamellar replacement can be reconstructed in vitro by cultivating human corneal epithelial cells and fibroblasts with an acellular porcine cornea matrix.This laid the foundation for the further transplantation in vitro.

Differentiation of human amniotic epithelial cells into corneal epithelial-like cells in vitro

·AIM: To explore the feasibility that human amniotic epithelial cells (hAECs) have the potential to differentiate into corneal epithelial -like cells under the microenvironment replicated by spontaneously immortalized human corneal epithelial cells (S-ihCECs). ·METHODS: hAECs were isolated by enzyme digestion, and flow cytometry was used to analysis the expression of CD29/90/166/73/34 and HLA -DR. Recovered and cultured S -ihCECs, immunocytochemistry was used to detect the expression of CK3/12. The proliferation of S - ihCECs handled by different concentrations of mitomycin was detected by CCK -8. The proliferation of hAECs cultured by S-ihCECs culture media collected at different time was analyzed by CCK -8. After filtered out the optimal conditions, we collected S-ihCECs culture media for 5 days, then prepared conditioned medium to incubate hAECs, inverted phase contrast microscope and scanning electron microscope were used to observe the change of morphology in hAECs. Quantitative real -time reverse transcription -polymerase chain reaction (QRT - PCR) was carried out to evaluate the expression of Oct - 4, NANOG, PAX6, and CK12 in the differentiation period. Immunocytochemistry and western bloting were used to detect the expression of CK3/12. ·RESULTS: The culture media collected every 12h, from 20μg/mL mitomycin pretreatment S -ihCECs could significantly promote the proliferation of hAECs. In the period of differentiation, the morphology of differentiated hAECs was obviously different compared with the control group, and the distinctive CK3/12 for corneal epithelial cells was detected.·CONCLUSION: This study showed that hAECs can differentiate into corneal epithelial -like cells by replication of the corneal epithelial microenvironment, using the culture media collected from S -ihCECs, and it is possible that S -ihCECs culture media could be used in corneal tissue engineering. ·

Adherent properties of Helicobacter pylori to human epithelial cells *

AIM To study the properties and factors of Helicobacter pylori adherence to human epithelial cells. METHODS The adherent properties of human epithelial cells were studied by using a group of isolated H. pylori strains, anti H. pylori monoclonal antibodies and varied pH environment in in vitro adherence model with HEp 2 cell.

Uptake of bacterial lipopolysaccharide and expression of tumor necrosis factor α mRNA in isolated rat intrahepatic bile duct epithelial cells *

AIM To study the uptake of bacterial lipopolysaccharides (LPS) and expression of tumor necrosis factor α mRNA (TNF α mRNA) with cultured rat intrahepatic bile duct epithelial cells.

Isolation, Cuture and Biological Characteristic Analysis of Stromal and Glandular Epithelial Cells of Buffalo (Bubalus bubalis) Endometrium

[Objective] The experiment aimed to set up a method for isolating and culturing endometrial stromal cells (BESC) and endometrial glandular epithelial cells(BEGEC) of buffalo as well as laid foundation for studying biological mechanism of embryo implantation and uterine diseases. [Method] The enzymatic digestion method, scraping method, serial filtration and differential velocity adherent technique were used to isolate BESC and BEGEC, then immunocytochemical method and TRYPAN-Blue assay were used to determine the purity and survival rate of isolated cells. [Result] The BESC and BEGEC were successfully isolated and cultured while immunocytochemical method and cell count method demonstrated that the purity was over 90%. The result of TRYPAN-Blue assay shown that survival rate of BESC and BEGEC was 91% and 78% respectively. [Conclusion] The enzymatic digestion method, scraping method, serial filtration and differential velocity adherent technique could isolate BESC and BEGEC with high purity.

Effect of Helicobacter pylori on gastric epithelial cells

The gastrointestinal epithelium has cells with features that make them a powerful line of defense in innate mucosal immunity. Features that allow gastrointestinal epithelial cells to contribute in innate defense include cell barrier integrity, cell turnover, autophagy, and innate immune responses. Helicobacter pylori (H. pylori) is a spiral shape gram negative bacterium that selectively colonizes the gastric epithelium of more than half of the world&#x02019;s population. The infection invariably becomes persistent due to highly specialized mechanisms that facilitate H. pylori&#x02019;s avoidance of this initial line of host defense as well as adaptive immune mechanisms. The host response is thus unsuccessful in clearing the infection and as a result becomes established as a persistent infection promoting chronic inflammation. In some individuals the associated inflammation contributes to ulcerogenesis or neoplasia. H. pylori has an array of different strategies to interact intimately with epithelial cells and manipulate their cellular processes and functions. Among the multiple aspects that H. pylori affects in gastric epithelial cells are their distribution of epithelial junctions, DNA damage, apoptosis, proliferation, stimulation of cytokine production, and cell transformation. Some of these processes are initiated as a result of the activation of signaling mechanisms activated on binding of H. pylori to cell surface receptors or via soluble virulence factors that gain access to the epithelium. The multiple responses by the epithelium to the infection contribute to pathogenesis associated with H. pylori.

Detection of H.pylori DNA in gastric epithelial cells by in situ hybridization

AIM: To investigate the presence of H.pylori DNA within gastric epithelial cells in patients with H.pylori infection and its possible carcinogenic mechanism. METHODS: Total 112 patients, with pathologically confirmed chronic superficial gastritis, chronic atrophic gastritis, intestinal metaplasia, atypical hyperplasia or gastric cancer were studied. Among them, 28 were H.pylori negative and 84 H.pylori positive. H.pylori DNA in gastric epithelial cells was detected by GenPoint catalyzed signal amplification system for in situ hybridization. RESULTS: In the H.pylori positive group, zero out of 24 chronic superficial gastritis (0.0%), four out of 25 precancerous changes (16.0%) and thirteen out of 35 gastric cancers (37.1%) showed H.pylori DNA in the nucleus of gastric epithelial cells, the positive rates of H.pylori DNA in the nucleus of gastric epithelial cells were progressively increased in chronic superficial gastritis, precancerous changes and gastric cancer groups (chi(2)=12.56, P=0.002); One out of 24 chronic superficial gastritis (4.2%), eleven out of 25 precancerous changes (44.0%) and thirteen out of 35 gastric cancers (37.1%) showed H.pylori DNA in the cytoplasm of gastric epithelial cells (chi(2)=10.86, P=0.004). In the H.pylori negative group, only one patient with gastric cancer was found H.pylori DNA in the nucleus of gastric epithelial cells; Only two patients, one patient with precancerous changes and another with gastric cancer, showed H.pylori DNA in the cytoplasm of gastric epithelial cells. Furthermore, H.pylori DNA must have been in the cytoplasm as long as it existed in the nucleus of gastric epithelial cells. CONCLUSION: H.pylori DNA exists both in the nucleus and the cytoplasm of gastric epithelial cells in patients with H.pylori infections. The pathological progression from chronic superficial gastritis, precancerous changes to gastric cancer is associated with higher positive rates of H.pylori DNA presence in the nucleus of gastric epithelial cells.

Intestinal epithelial cells in inflammatory bowel diseases

The pathogenesis of inflammatory bowel diseases (IBDs) seems to involve a primary defect in one or more of the elements responsible for the maintenance of intestinal homeostasis and oral tolerance. The most important element is represented by the intestinal barrier, a complex system formed mostly by intestinal epithelial cells (IECs). IECs have an active role in producing mucus and regulating its composition; they provide a physical barrier capable of controlling antigen traff ic through the intestinal mucosa. At the same time, they are able to play the role of non-professional antigen presenting cells, by processing and presenting antigens directly to the cells of the intestinal immune system. On the other hand, immune cells regulate epithelial growth and differentiation, producing a continuous bi-directional cross-talk within the barrier. Several alterations of the barrier function have been identif ied in IBD, starting from mucus features up to its components, from epithelial junctions up to the Toll-like receptors, and altered immune responses. It remains to be understood whether these defects are primary causes of epithelial damage or secondary effects. We review the possible role of the epithelial barrier and particularly describe the role of IECs in the pathogenesis of IBD.

Parthenolide protects human lens epithelial cells from oxidative stress-induced apoptosis via inhibition of activation of caspase-3 and caspase-9

The apoptosis of lens epithehal cells has been proposed as the common basis of cataract formation, with oxidative stress as the major cause. This study was performed to investigate the protective effect of the herbal constituent parthenolide against oxidative stress-induced apoptosis of human lens epithelial （HLE） cells and the possible molecular mechanisms involved. HLE cells （SRA01-04） were incubated with 50 μM H2O2 in the absence or presence of different doses of parthenolide （10, 20 and 50 μM）. To study apoptosis, the cells were assessed by morphologic examination and Annexin V-propidium iodide double staining flow cytometry; to investigate the underlying molecular mechanisms, the expression of caspase-3 and caspase-9 were assayed by Western blot and quantitative RT-PCR, and the activities of caspase-3 and caspase-9 were measured by a Chemicon caspase colorimetric activity assay kit. Stimulated with H202 for 18 h, a high fraction of riLE cells underwent apoptosis, while in the presence ofparthenolide of different concentrations, dose-dependent blocking of HLE cell apoptosis was observed. The expression of caspase-3 and caspase-9 induced by H202 in HLE cells was significantly reduced by parthenolide both at the protein and mRNA levels, and the activation ofcaspase-3 and caspase-9 was also suppressed by parthenolide in a dose-dependent manner. In conclusion, parthenolide prevents HLE cells from oxidative stress-induced apoptosis through inhibition of the activation ofcaspase-3 and caspase-9, suggesting a potential protective effect against cataract formation.

Influence on Cellular Signal Transduction Pathway in Dairy Cow Mammary Gland Epithelial Cells by Galactopoietic Compound Isolated from Vaccariae segetalis

The galactopoietic mechanism of Vaccaria segetalis is still unknown. Understanding dibutyl phthalate （DBP） separated from Vaccaria segetalis on the expression of lactation signal transduction genes of mammary gland epithelial cells, including prlr, erα, akt1, socs2, pparγ and elf5, will be helpful to reveal the molecular mechanism. Western blot and qRT- PCR were used to study the change of prlr, erα, akt, socs2, pparγ, and elf5 expression at mRNA and protein level. Co- localization expression of prolactin receptor （PRLR） and estrogen receptor α （ERα） was observed by immunofluorescence; the expression changes of miRNAs （21, 125b, 143, and 195） and the secretion of β-casein and lactose were detected by qRT-PCR and RP-HPLC. The results showed that Vaccaria segetalis active compound had similar fuctions as estrogen and/or prolactin （PRL） in dairy cow mammary gland epithelial cells （DCMECs）, increased the expressions of prlr, erα, akt1, and elf5 genes, while repressed pparγ expressions. DBP promoted socs2 mRNA expression, but its protein expressions were repressed. Furthermore, both DBP and PRL could repress the expressions of miRNA-125b, miRNA-143 and miRNA- 195 in DCMECs. DBP could repress the expression of miRNA-21, while the influence of PRL on miRNA-21 was not certain. DBP could promote the lactation ability of DCMECs by regulating the ER and PRLR cellular signal transduction pathway.