Effects of epidermal growth factor and insulin on migration and proliferation of primary cultured rabbit gastric epithelial cells.

We assessed the influence of epidermal growth factor (EGF) and insulin on gastric epithelial restoration in vitro. Rabbit gastric epithelial cells were cultured and formed a complete monolayer cell sheet in 2 days. We created a wound (1.8 +/- 0.05 mm2) by denuding an area of cells, and EGF (0.1-30 ng/ml) and/or insulin (1 nM-1 microM) was added. The restoration process, which included cell migration and proliferation, was monitored by measuring the cell-free area every 12 h for 2 days. Proliferating cells were detected by sequential staining with bromodeoxyuridine (BrdU). Control cells showed complete repair in 36-48 h and restoration was accelerated dose-dependently by EGF or insulin. EGF plus insulin further accelerated restoration, which was then completed in 12-24 h. EGF and/or insulin increased the number of BrdU- positive cells. The results indicated that EGF and insulin additively accelerated gastric epithelial wound repair by stimulating both the migration and the proliferation of gastric epithelial cells (particularly the former).

[A case of advanced gastric cancer remarkably responding to preoperative UFT-E therapy].

We here reported a case of advanced gastric cancer remarkably responding to preoperative short-term UFT-E chemotherapy. UFT-E was orally administered preoperatively for about a month to the patient with type 2 advanced gastric cancer. After the chemotherapy the cancer was found to be remarkably decreased in size and denatured. The amount of residual cancer cells was limited by histopathological examination following the operation and diagnosed as Grade 3 based on the criteria of histological evaluation of chemotherapy for cancer. We continued to administer UFT-E postoperatively and the patient is still alive without symptoms.

Evaluation of ethanol on gastric epithelial restoration in vitro.

Ethanol exerts damaging effects on gastric mucosa and delays ulcer healing. To investigate the effect of ethanol on the wound repairing process, we used a wound repair model using primary cultured gastric mucosal cells. A confluent monolayer gastric mucosal cell sheet consisting mainly of mucous cells was wounded to make a cell-free area of constant size. Cell-free area was restored with time after wounding and monitored every 12 hr using a computer image analyzer to observe epithelial cell restoration quantitatively in the presence and absence of ethanol (2.0%). It was found that, although the control wound was completely repaired in 36 to 48 hr, the group treated with 2.0% ethanol showed a significant delay of repair. In the control, 5-bromodeoxyuridine-positive cells appeared around the wound in 24 to 36 hr. In contrast, the group treated with 2.0% ethanol showed no 5-bromodeoxyuridine-positive cells during the experiment. In conclusion, 2.0% ethanol retarded the repair of gastric mucosal restoration by inhibiting the initial gastric cell migration, followed by inhibition of proliferation of cells.

A new model to study repair of gastric mucosa using primary cultured rabbit gastric epithelial cells.

The process of wound repair was investigated using primary cultured rabbit gastric mucosal cells. A confluent monolayer gastric mucosal cell sheet consisting mainly of mucous cells was wounded to make a cell-free area of constant size. The changes in the cell-free area were analyzed quantitatively by image analysis. The wound recovered in 36-48 h in controls; wound repair was accelerated by the addition of fetal calf serum (FCS) and hepatocyte growth factor (HGF) to the medium and was retarded by inhibitors of cytoskeletal proteins. In the process of normal wound repair, 5-bromodeoxyuridine (BrdU)-positive cells appeared around the wound in 24-36 h but disappeared after complete repair. In the FCS- and HGF-treated group, BrdU-positive cells were mainly detected 12-24 h after wounding. In this model the wound was repaired in two steps: an initial cell migration stage and a later proliferation stage. In conclusion, FCS and some growth factors accelerate wound repair with the induction of both epithelial cell migration and proliferation. The cytoskeletal system plays an important role in normal gastric restoration.

Hepatocyte growth factor accelerates the wound repair of cultured gastric mucosal cells.

Effects of hepatocyte growth factor (HGF) on gastric wound repair were assessed. Artificial wounds of uniform size were made by mechanical cell denudation in confluent rabbit gastric mucosal cell sheets. The changes in wound size were analyzed quantitatively. The wound repair process contained an initial migration stage and a later proliferation stage. The wound was completely repaired in 36 h in controls; this repair was accelerated by HGF with the induction of cell migration followed by proliferation and was retarded by tyrosine protein kinase inhibitor genistein. HGF might play some roles in gastric ulcer healing.

Effect of nicotine in migration and proliferation of rabbit gastric mucosal cells in a culture cell model.

The aim of this study was to assess the effects of nicotine on the gastric epithelial restoration using primary cultured rabbit gastric mucosal cell model. Confluent monolayer mucosal cell sheets consisting of mainly mucous cells were wounded using a rotating silicon tip. The process of restoration was monitored, and the size of wound was measured and analysed quantitatively. Artificial wounds recovered in 36 h in controls. The nicotine treatment (10(-5), 10(-4) and 10(-3) mol/L) did not cause any effects on the process of wound repair. Bromodeoxyuridine (BrdU) positive cells appeared around the wound 24-36 h after injury and then disappeared after the complete repair in controls and also in nicotine-treated groups. However, in the morphological observation, numerous vacuoles were detected in parietal cells of nicotine-treated groups. This effect of nicotine was reversible by removing nicotine from the medium. Present data suggest that nicotine has no direct effects on the mucosal restoration but might have an effect on the structure and function of parietal cells.