[Gene polymorphisms of cytochrome B-245 alpha chain (CYBA) and cholesteryl ester transfer protein (CETP) and susceptibility to generalized aggressive periodontitis].

OBJECTIVE: To explore the correlation of cytochrome B-245 alpha chain (CYBA) rs4673 and cholesteryl ester transfer protein (CETP) rs12720922 polymorphisms with the susceptibility of gene-ralized aggressive periodontitis (GAgP). METHODS: The study was a case-control trial. A total of 372 GAgP patients and 133 periodontally healthy controls were recruited. The CYBA rs4673 and CETP rs12720922 polymorphisms were detected by matrix assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF-MS). Logistic regression models were used to analyze the correlation of CYBA rs4673 and CETP rs12720922 variants with the susceptibility of GAgP. The interaction between the two gene polymorphisms to the susceptibility of GAgP was analyzed by the likelihood ratio test. The interaction model adopted was the multiplication model. RESULTS: The mean age of GAgP group and control group was (27.5±5.2) years and (28.8±7.1) years respectively. There was significant difference in age between the two groups (P < 0.05). The gender distribution (male/female) was 152/220 and 53/80 respectively, and there was no significant difference between GAgP group and controls (P>0.05). For CYBA rs4673, the frequency of CT/TT genotype in the GAgP group was significantly higher than that in the controls [18.0% (66/366) vs. 10.6% (14/132), P < 0.05]. After adjusting age and gender, the individuals with CT/TT genotype had a higher risk of GAgP (OR=1.86, 95%CI: 1.01-3.45, P < 0.05), compared with CC genotype. There was no statistically significant difference in distributions of the CETP rs12720922 genotypes (GG, AA/AG) between GAgP patients and healthy controls (P>0.05). A significant interaction between CYBA rs4673 and CETP rs12720922 in the susceptibility to GAgP was observed. The GAgP risk of the individuals with CYBA rs4673 CT/TT and CETP rs12720922 GG genotypes was significantly increased (OR=3.25, 95%CI: 1.36-7.75, P < 0.01), compared with those carrying CC and AA/AG genotypes. CONCLUSION: CYBA rs4673 CT/TT genotype is associated with GAgP susceptibility. There is a significant interaction between CYBA rs4673 CT/TT genotype and CETP rs12720922 GG genotype in the susceptibility of GAgP.

[Interaction analysis between epidermal growth factor and peroxidase proliferators activate receptor-α gene polymorphism and susceptibility to generalized aggressive periodontitis].

Objective: To explore the correlation and interaction between epidermal growth factor (EGF) rs2237051 and peroxidase proliferators activate receptor-α (PPAR-α) rs4253623 polymorphisms and the susceptibility of generalized aggressive periodontitis (GAgP). Methods: Two hundred and nineteen Chinese patients with GAgP were enrolled from the patients of the Department of Periodontology, Peking University School and Hospital of Stomatology from January 2001 to December 2015. The control group comprised 138 periodontally healthy volunteers recruited from the staff and students of the Peking University School and Hospital of Stomatology. The EGF rs2237051 and PPAR-α rs4253623 polymorphisms were genotyped using time-of-flight mass spectrometry. Logistic regression models were conducted to analyze the correlation between the EGF rs2237051 and PPAR-α rs4253623 variants with GAgP. The likelihood ratio test was used to analyze whether there was an interaction between the two polymorphisms in the susceptibility of GAgP. The interaction model adopted was the multiplication model. Results: The mean ages of GAgP group (male:87; female:132) and control group (male: 53; female: 85) were (27.3±4.5) years and (27.1±4.2) years respectively and there was no significant difference in age and gender distribution between the two groups. For EGF rs2237051, the frequency of AA genotype in the GAgP group [49.5% (107/216)] was significantly higher than that in the control group [37.7% (52/138)], and the frequency of AG/GG genotype in the GAgP group [50.5% (109/216)] was significantly lower than that in the control group [62.3% (86/138)](P<0.05). Compared with AA genotype, individuals with AG/GG genotype had a 39% lower risk of GAgP after adjustment of age and gender (OR: 0.61, 95%CI: 0.40-0.95, P<0.05). For PPAR-α rs4253623, the frequency of AA genotype in the GAgP group [76.2% (160/210)] was significantly higher than that in the control group [65.9%(81/123)], and the frequency of AG/GG genotype in the GAgP group [23.8% (50/210)] was significantly lower than that in the control group [34.1%(42/123)] (P<0.05). Compared with AA genotype, individuals with AG/GG genotype had a 40% lower risk of GAgP after adjustment of age and gender (OR: 0.60, 95%CI: 0.36-0.98, P<0.05). EGF rs2237051 and PPAR-α rs4253623 showed a significant interaction in the susceptibility to GAgP. Compared with AA genotype, the risk of GAgP in individuals with both AG/GG genotypes of EGF rs2237051 and PPAR-α rs4253623 was reduced by 66% (OR: 0.34, 95%CI: 0.17-0.66, P<0.01). Conclusions: EGF rs2237051 and PPAR-α rs4253623 are correlated with GAgP susceptibility, and there is a significant interaction between them in the susceptibility of GAgP. The G allele of the two loci has a protective effect on the disease of GAgP.

[Clinical outcomes of ultrasonic subgingival debridement combined with manual root planing in severe periodontitis].

OBJECTIVE: To compare the clinical effects of ultrasonic subgingival debridement and ultrasonic subgingival debridement combined with manual root planing on severe periodontitis and then to investigate the necessity and significance of manual root planing. METHODS: Twenty-three patients with severe periodontitis participated in this split-mouth randomized-controlled clinical trial. Baseline examination and randomization were performed after supragingival scaling: each of the upper and lower jaws had a quadrant as the test group treated with ultrasonic subgingival debridement combined with manual root planing, whereas the other two quadrants were the control group treated with ultrasonic subgingival debridement. Treatment of each patient was at intervals of one week and completed in two visits. Clinical indicators concerning probing depth (PD), clinical attachment loss (CAL) and bleeding index (BI) were recorded at baseline and 1 month, 3 months, 6 months after treatment. RESULTS: There was no significant difference of periodontal indicators between the test group and the control group at baseline. Both the test group and control group resulted in significant improvement of PD, CAL and BI. One and three months after treatment, reduction of PD in the test group was higher than that in the control group [1 month: (2.13±1.31) mm vs. (1.79±1.33) mm, P<0.01; 3 months: (2.46±1.33) mm vs. (2.17±1.38) mm, P<0.01] and reduction of CAL in the test group was higher than that in the control group [1 month: (1.89±2.03) mm vs. (1.65±1.93) mm, P<0.01; 3 months: (2.03±2.05) mm vs. (1.83±1.97) mm, P<0.05]. Six months after treatment, PD in the test group and the control group decreased by (2.52±1.40) mm and (2.35±1.37) mm respectively, and the improvement in the test group was significantly better than that in the control group (P<0.01). CAL in the test group and the control group decreased by (1.89±2.14) mm and (1.77±2.00) mm respectively, and there was no statistical difference between the groups. There was no significant difference in the changes of BI between the two groups 1, 3 and 6 months after treatment. CONCLUSION: Ultrasonic subgingival debridement combined with manual root planing has more reduction in PD and CAL compared with ultrasonic subgingival debridement. Therefore, it is still necessary to use manual instruments for root planing following ultrasonic subgingival debridement.

[Association between root abnormalities and related pathogenic genes in patients with generalized aggressive periodontitis].

OBJECTIVE: To explore the association between the abnormal root morphology and bone metabolism or root development related gene polymorphism in patients with generalized aggressive periodontitis. METHODS: In the study, 179 patients with generalized aggressive periodontitis were enrolled, with an average age of (27.23±5.19) years, male / female = 67/112. The average number of teeth remaining in the mouth was (26.80±1.84). Thirteen single nucleotide polymorphisms (SNPs) of nine genes which related to bone metabolism and root development were detected by matrix assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF-MS). Root abnormalities were identified using periapical radiographs. The abnormal root morphology included cone-rooted teeth, slender-root teeth, short-rooted teeth, curved-rooted teeth, syncretic-rooted molars, and molar root abnormalities. The number of teeth and incidence of abnormal root morphology in different genotypes of 13 SNPs were analyzed. RESULTS: The constituent ratio of root with root abnormality in GAgP patients was 14.49%(695/4 798). The average number of teeth with abnormal root morphology in GAgP was (3.88±3.84). The average number of teeth with abnormal root morphology in CC, CT and TT genotypes in vitamin D receptor (VDR) rs2228570 was (4.66±4.10), (3.71±3.93) and (2.68±2.68). There was significant difference between TT genotype and CC genotype (t = 2.62, P =0.01). The average number of root morphological abnormalities in CC, CT and TT genotypes of Calcitotin Receptor (CTR) gene rs2283002 was (5.02±3.70), (3.43±3.95), and (3.05±3.12). The incidence of root morphological abnormalities in CC genotype was higher than that in the patients with CT and TT, and the difference was statistically significant(87.86% vs. 65.26% & 63.64%, P=0.006, adjusted OR =3.71, 95%CI: 1.45-9.50). There was no significant difference in the incidence of abnormal root morphology between CT and TT genotypes. CONCLUSION: VDR rs2228570 and CTR rs2283002 may be associated with the occurrence of abnormal root morphology in patients with generalized aggressive periodontitis, which is worthy of further research.

[Efficacy of subgingival glycine air polishing on patients with early peri-implant diseases].

Objective: To compare the clinical efficacies of subgingival glycine air polishing and ultrasonic scaling combined with 0.12% chlorhexidine rinsing on patients with early peri-implant diseases (peri-implant mucositis and early peri-implantitis). Methods: Twenty-two systemically healthy patients with totally 42 implants and early peri-implant diseases, were recruited in this study. The patients were randomly divided into the test group and the control group. Patients in the test group were treated with subgingival glycine air polishing and patients in the control group were treated with ultrasonic scalers combined with 0.12% chlorhexidine rinsing. Periodontal parameters such as probing depth, bleeding index, plaque index and clinical attachment loss, at baseline and 2 months after treatment, respectively, were collected and compared between the test and control groups. Results: For the natural teeth, the parameters of probing depth, bleeding index, plaque index and attachment loss in the two groups were significantly improved after treatments (medians were 0.48 mm vs 0.22 mm, 1.00 vs-0.13, 0.38 vs 0.50, 0.48 mm vs 0.22 mm, respectively for test and control group). There was no statistical difference of median between the two groups after treatment except for that of the attachment loss (medians, 0.48 mm vs 0.22 mm, P=0.034). For the implants, differences of parameters in the two groups at baseline were insignificant. After treatments, the probing depths significantly decreased by 0.67 mm and 0.33 mm in the test group and the control group, respectively. The inter-group differences, however, were insignificant. Significant difference of the bleeding index after treatment was found in the test group (P=0.019), but not in the control group. No adverse reactions were found on patients in the two groups after treatments. Conclusions: Efficacy of subgingival glycine air polishing and ultrasonic scaling combined with 0.12% chlorhexidine rinsing is competitive on patients with early peri-implant diseases. However, the former treatment may be more effective oncontrolling the early peri-implant inflammation.

Comparison of the molecular interactions of 7'-carboxyalkyl apigenin derivatives with S. cerevisiae α-glucosidase.

As one of the most investigated flavonoids, apigenin, is considered to be a strong α-glucosidase inhibitor. However, the clinical utility of apigenin is limited due to its low solubility. It was reported that the solubility and biological activity can be improved by introducing sole carboxyalkyl group into apigenin, especially the 7'-substitution. With the increase of length of the alkyl chain in carboxyalkyl group, B ring of the apigenin derivative is embedded much more deeply into the binding cavity while the carboxyalkyl stretches to the neighboring cavity. All of the terminal carboxyl groups form hydrogen bonding interactions easily with the surrounding polar amino acids, such as His239, Ser244, Arg312 and Asp349. Thus, the electron density values of the carbonyl in the carboxyl group become higher than the solution status due to the strong molecular interactions. In fact, electron densities of most of the chemical bonds are decreased after molecular docking procedure. On compared with the solution phase, however, dipole moments of most of these molecules are increased, and their vectors are reoriented distinctly in the active sites. It is noticed that all of the Highest Occupied Molecular Orbital (HOMO) and Lowest Unoccupied Molecular Orbital (LUMO) are distributed throughout the whole parent apigenin ring in solution phase, whereas the disappeared situation happened on the B rings of some molecules (II-IV) in the active site, leading to higher energy gaps.

Concurrent chemotherapy and adjuvant extended field irradiation after radical surgery for cervical cancer patients with lymph node metastases.

The purpose of this retrospective study was to report our experience with concurrent chemotherapy and adjuvant extended field irradiation after radical surgery for cervical carcinoma patients with common iliac node and/or multiple pelvic lymph nodes metastases. We studied 25 patients with FIGO stage IB-IIB (IB, 3; IIA, 15; and IIB, 7) cervical carcinoma who underwent radical surgery and had histologically confirmed involvement of common iliac nodes and/or multiple (>or=2) pelvic lymph nodes. These patients received the first cycle of systemic chemotherapy 2 weeks after radical surgery. Then, they received pelvic and extended field irradiation (40-45 Gy) with weekly cisplatinum (30 mg/m(2)). They were then given five more cycles of consolidation chemotherapy. Survival curves were generated by the Kaplan-Meier method. The 3-year progression-free survival (PFS) and overall survival rates were 63% and 76%, respectively. The PFS rates with multiple pelvic node and common iliac node metastases were 69% and 61%, respectively. The pelvic recurrence rate was 8% (2/25) and that for distant metastases was 32% (8/25). No patient's treatment failed in the para-aortic region. The median interval from the surgery to the recurrence was 14 months (range, 5-29 months). Nineteen (76%) patients experienced grades 1-2 and four (16%) experienced grades 3-4 neutropenia. Fifteen patients (60%) experienced grades 1-2 and one (4%) experienced grades 3-4 gastrointestinal toxicity. Concurrent chemotherapy and adjuvant extended field irradiation after radical surgery achieved good local control with acceptable toxicity. However, subsequent distant metastasis was still the predominant form of treatment failure even after consolidation chemotherapy.

Proteomic analysis of low-abundant integral plasma membrane proteins based on gels.

To characterize low-copy integral membrane proteins and offer some methods for human liver proteome projects, we fractionated highly purified rat liver plasma membrane (PM). PM was purified through two sucrose density gradient centrifugations, and treated with 0.1 M Na(2)CO(3), chloroform/methanol and Triton X-100. Proteins were separated by electrophoresis and submitted to mass spectrometry analysis. Four hundred and fifty-seven non-redundant membrane proteins were identified, of which 23% (105) were integral membrane proteins with one or more transmembrane domains. One hundred and fifty-three (33.5%) had no location annotation and 68 were unknown-function proteins. The proteins from different fractions were complementory. A database search for all identified proteins revealed that 53 proteins were involved in the cell communication pathway. More interestingly, more than 50% of the proteins had a protein abundance index concentration of less than 0.1 mol/l, and 12% proteins a concentration 100 times less than that of arginase 1 and actin.

Neuroreceptors and ion channels as targets of alcohol.

This article represents the proceedings of a symposium at the 2000 ISBRA Meeting in Yokohama, Japan. The chairs were Toshio Narahashi and Kinya Kuriyama. The presentations were (1) Modulation of neuroreceptors and ion channels by alcohol, by T. Narahashi; (2) Inhibition by ethanol of NMDA and AMPA receptor-channels, by P. Illes, K. Wirkner, W. Fischer, K. Mühlberg, P. Scheibler, and C. Allgaier; (3) Effects of ethanol on metabotropic glutamate receptors, by K. Minami; (4) Acute alcohol actions on the 5-HT3 ligand-gated ion channel, by D. Lovinger; (5) Inhibition of NMDA receptors by MK801 attenuates ethanol-induced taurine release from the hippocampus, by F. Lallemand, R.J. Ward, and P. DeWitte; and (6) Effect of ethanol on voltage-operated Ca2+ channels in hepatic stellate cells, by T. Itatsu, Y. Takei, H. Oide, M. Hirose, X. E. Wang, S. Watanabe, M. Tateyama, R. Ochi, and N. Sato.

[RFLP analysis of wheat-L. racemosus translocation lines].

A number of wheat-L. racemosus translocation lines were developed by irradiation, pollen culture and gametocidal chromosome methods. In order to identify homozygous translocation lines and determine the exact location of the breakpoints involved in the translocations, 67 probes genetically or physically mapped previously on wheat chromosomes belonging to seven homoeologous groups were used for RFLP analysis. Three homozygous translocation lines were identified: T1BL.7Lr # 1S, T4BS.4BL-7Lr # 1 and T6AL.7Lr # 1S. In lines T1BL.7Lr # 1S and T6AL.7Lr # 1S, the breakpoint of chromosome 7Lr # 1 was located in the short arm between the area marked by clone MWG808 and that of ABG476.1, and the breakpoints of chromosomes 1B and 6A were both located near the centromere. In line T4BS.4BL-7Lr # 1S, the breakpoint of chromosome 7Lr # 1 was located in the short arm between the area marked by clone BCD349 and that of CDO595, the breakpoint of chromosome 4B was located in the long arm between the area marked by clone CDO541 and that of PSR164.

Acute and chronic effect of alcohol on Ca2+ channels in hepatic stellate cells.

BACKGROUND: Hepatic stellate cells have been reported to play important roles in the regulation of hepatic microcirculation via cell contraction. Increase in intracellular calcium concentration is required to induce cell contraction. We have already reported the existence of L-type voltage-operated Ca2+ channels (VOCC), such as smooth muscle cells. On the other hand, alcohol has been known to disturb hepatic microcirculation. In this study, we evaluated the effect of acute and chronic treatment of alcohol on VOCC in rat hepatic stellate cells. METHODS: Stellate cells isolated from rats were cultured with or without 100 mM ethanol for up to 14 days. VOCC were detected by the patch clamp technique. Cells cultured for 14 days without ethanol were exposed to ethanol to investigate calcium current during membrane depolarization. alpha-Smooth muscle actin (alpha-SMA) was stained by indirect immunofluorescence. RESULTS: In the control model, VOCC were recognized in cells cultured for more than 7 days. Detection of VOCC increased from 9% on day 7 to 55% on day 14. On the other hand, VOCC in cells treated chronically with 100 mM ethanol appeared earlier than in the control and the incidences were significantly higher than those of the control accompanied with an early activation of cells. In contrast, simultaneous exposure to ethanol during the membrane depolarization inhibited Ca2+ current. CONCLUSIONS: The expression of Ca2+ channels in stellate cells were up-regulated by the chronic treatment of alcohol accompanied with the transformation to myofibroblast-like phenotype. However, alcohol itself inhibited Ca2+ current.

Epithelial-mesenchymal interaction in gastric mucosal restoration.

In this review article we discuss the role of growth factors in gastric ulcer healing using an in vitro wound repair model with gastric epithelial and mesenchymal cells. Several growth factors accelerate gastric epithelial and mesenchymal wound healing in vitro with acceleration of cell migration and proliferation. Epidermal growth factor, transforming growth factor-alpha (TGFalpha), hepatocyte growth factor, and insulin accelerate predominantly gastric epithelial wound healing; and TGFbeta and basic fibroblast growth factor predominantly accelerate gastric mesenchymal wound healing. Platelet-derived growth factor-betabeta and insulin-like growth factor-1 (IGF-1) accelerate both significantly. Among these growth factors, IGF-1 produced from fibroblasts plays a key role in the gastric epithelial-mesenchymal interaction during the process of gastric wound healing.

Activated stellate (Ito) cells possess voltage-activated calcium current.

We previously reported stellate (Ito) cells possess voltage-activated Ca2+ current. The activation of stellate cells has been indicated to contribute to liver fibrosis and the regulation of hepatic hemodynamics. The aim of this study was to investigate the relationship between voltage-activated Ca2+ current and activation of stellate cells. Voltage-activated Ca2+ current in stellate cells isolated from rats were studied using whole-cell patch clamp technique. L-type voltage-activated Ca2+ current was hardly detected in stellate cells cultured for less than 9 days. Ca2+ current was detected 12.5 and 69% of cells at the 10th and 14th day of culture, respectively. BrdU incorporation indicated cell proliferation was recognized over 50% of cells at the 3rd and 5th day of culture, respectively, then decreased significantly in a time-dependent manner. On the other hand, the expression of alpha-smooth muscle actin indicated cell activation increased from 7th day of culture and collagen type I mRNA appeared remarkably in cells cultured for more than 10 days. In this study, we concluded L-type voltage-activated Ca2+ current was recognized in activated stellate (myofibroblast-like) cells.

Insulin-like growth factor I plays a role in gastric wound healing: evidence using a zinc derivative, polaprezinc, and an in vitro rabbit wound repair model.

BACKGROUND: Although the detailed mechanism is unclear, zinc and its derivative, polaprezinc, have been reported to accelerate gastric ulcer healing in vivo. AIM: To investigate the detailed cellular mechanism of polaprezinc on gastric epithelial cells and fibroblasts with special attention to insulin-like growth factor I (IGF-I). METHODS: Isolated rabbit gastric epithelial cells formed a complete monolayer, from which a circular artificial wound with constant size was made. The restoration process was monitored by measuring wound size up to 48 h. Either polaprezinc, IGF-I, fibroblast conditioned medium or neutralized medium conditioned by anti-IGF-I antibody was added at the time of wounding. The expression of mRNA of IGF-I, hepatocyte growth factor (HGF) and transforming growth factor alpha (TGF-alpha) in fibroblasts with or without polaprezinc treatment was tested using reverse transcription polymerase chain reaction (RT-PCR). Gastric epithelial cell proliferation was also examined by bromodeoxyuridine (BrdU) staining. RESULTS: IGF-I and fibroblast conditioned medium treatment accelerated gastric epithelial restoration which included cell migration and proliferation. However, polaprezinc and neutralized conditioned medium treatment did not accelerate epithelial repair. RT-PCR for growth factor mRNA revealed the IGF-I mRNA expression in fibroblasts was increased after treatment with polaprezinc. CONCLUSION: Polaprezinc induced IGF-I production from mesenchymal cells, resulting in stimulation of epithelial cell restoration through a paracrine pathway. IGF-I may play an important role in gastric wound repair.

Hepatic stellate cell contraction is inhibited by lipo-prostaglandin E1 in vitro.

Prostaglandin E1 (PGE1) has been reported to have, experimentally and clinically, a protective effect against liver damage. This effect may result from the relaxation of hepatic stellate cells, whose contraction induces vasoconstriction of hepatic sinusoids. However, prostaglandins are unstable and a new drug delivery system is necessary to administer a sufficient amount of prostaglandin to achieve a protective effect in the liver. The aim of the study is to investigate the effects of lipo-prostaglandin E1 (lipo-PGE1) which has a novel drug delivery system on the stellate cell contraction induced by endothelin-1 in vitro. Lipo-PGE1 inhibited endothelin-1-induced stellate cell contraction in concentrations of 10, 30 and 50 ng/mL. Therefore, lipo-PGE1 may show a cytoprotective effect in the liver through the relaxation of stellate cells and an increase in the hepatic sinusoidal blood flow.

A novel hepatic stellate (Ito) cell-derived protein, epimorphin, plays a key role in the late stages of liver regeneration.

Limited data exist regarding morphogenesis and differentiation during liver regeneration. We examined the role of epimorphin on liver regeneration. After 70% partial hepatectomy, mouse liver was collected on days 1, 3, 7, and 14 for immunohistochemistry and the detection of epimorphin mRNA and connexin 32. Using primary cultured rat hepatocytes, morphogenesis and differentiation of cells were tested with or without epimorphin. Seven days after cell inoculation, the expression of connexin 32 and the cell-cell communication was tested as a marker of differentiation. Epimorphin was detected exclusively in hepatic stellate cells. Connexin 32 was detected only in hepatocytes. After partial hepatectomy, epimorphin mRNA was detected on day 3 and peaked at day 7, followed by protein expression. Connexin 32 expression showed a similar time course. Cultured hepatocytes formed multicellular spheroids in an active epimorphin-coated culture dish and showed positive dye coupling, whereas the cell-cell communication was lost without active epimorphin. Because epimorphin was expressed late in liver regeneration, it might play a role in morphogenesis and differentiation.

Rebamipide prevented delay of wound repair induced by hydrogen peroxide and suppressed apoptosis of gastric epithelial cells in vitro.

The effects of rebamipide on the restoration process of gastric epithelial wounds were assessed using an in vitro wound-healing model and hydrogen peroxide treatment. Rebamipide (10 or 100 microM) was added to a complete monolayer cell sheet after artificial wounding. The restoration process was analyzed sequentially by a time-lapse video system, and cell migration, proliferation, and apoptosis were assessed. Hydrogen peroxide (1 or 3 mM) inhibited restoration after wounding by suppressing cell migration and proliferation. It also induced epithelial cell apoptosis around the wound. The addition of rebamipide abolished the H2O2-induced retardation and prevented apoptosis. Rebamipide might act as a radical scavenger and have favorable effects on peptic ulcer diseases.

Effects of teprenone on gastric epithelial restoration in a rabbit cultured cell model.

The mechanism of action of gastrocytoprotective agents is not fully understood. We assessed the effects of an anti-ulcer agent, teprenone, and bile acid on epithelial restoration. Teprenone with or without deoxycholic acid was added to a complete confluent cultured gastric epithelial cell sheet after wounding. Restoration was monitored for 48 h, and the wound size was assessed. Migration velocity was measured, and proliferation was detected by sequential staining with bromodeoxyuridine. The labeling index was calculated. Restoration was completed within 48h in controls, whereas deoxycholic acid retarded repair. The migration velocity was suppressed by deoxycholic acid treatment. The number of proliferative cells peaked at 36 h (labeling index, 1.7%) in controls. In the deoxycholic acid group, the maximal labeling index was 0.5% at 48 h. Teprenone abolished the bile acid-induced retardation. Teprenone showed cytoprotective effects against deoxycholic acid-induced inhibition of epithelial cell migration and proliferation.

A neurotrophic pyrimidine compound, MS-818, enhances EGF-induced restoration of gastric epithelial wounds in vitro.

MS-818 is a novel synthetic pyrimidine compound that stimulates nerve regeneration and promotes synthesis of various growth factors and differentiation of astrocytes. Effects of MS-818 on gastric epithelial cells were assessed using a wound repair model with primary cultured gastric epithelial cells from rabbits. A round wound with a constant cell-free area was created and the process of restoration was monitored by measuring wound size every 12 h. Cell proliferation was monitored by sequential staining with BrdU. As previously reported, EGF (10 ng/ml) accelerated wound repair by promoting cell migration and proliferation. Although MS-818 alone had no effects, MS-818 (10-100 microM) enhanced EGF-induced acceleration of gastric epithelial restoration, including cell migration and proliferation. Although the detailed mechanism of action of this agent is still unclear, MS-818 might have favorable effects on in vivo gastric mucosal repair.

Effects of rebamipide on bile acid-induced inhibition of gastric epithelial repair in a rabbit cell culture model.

BACKGROUND: Anti-ulcer agents exert various functional effects on gastric epithelial cells. AIM: The effects of a novel gastro-cytoprotective agent (rebamipide) on epithelial restoration following bile acid damage were assessed using primary cultured rabbit gastric epithelial cells. METHODS: Rebamipide was added to complete confluent cell sheets with deoxycholic acid just after creating a cell-free wound (2 mm2). The restoration was monitored and analysed by phase contrast microscopy and an image analyser for 48 h. The migration speed was measured during the initial 3 h after wounding. Cell proliferation was detected by staining for bromodeoxyuridine (BrdU) at 12-h intervals. The labelling index was calculated per unit area. The major cytoskeletal protein actin was detected by immunohistochemical staining. RESULTS: In the controls, restoration was completed 48 h following wounding. Deoxycholic acid retarded this process. The addition of rebamipide to deoxycholic acid abolished the bile acid-induced retardation. The migration speed was 26 microns/h in the controls. 15 microns/h in the deoxycholic acid group and 27 microns/h in the deoxycholic acid plus rebamipide group. In the controls, BrdU-positive cells, which were rarely detected in the initial 24 h, were maximal at 36 h (labelling index 1.7%). In the deoxycholic acid group, proliferation was inhibited (peak labeling index; 0.5% at 48 h). Actin-containing stress fibres were detected throughout the cells and the periphery of the lamellipodia in the controls, and were disrupted in the deoxycholic acid-treated group. Rebamipide prevented these effects. CONCLUSIONS: Deoxycholic acid significantly retarded restoration by the inhibition of both cell migration and proliferation, potentially through an effect on the cytoskeleton. Rebamipide protected the mucosal cells from bile acid mediated injury.