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Background and Aims: Hydrotalcite plays an important role in the therapy of gastric ulcer induced by nonsteroidal anti-inflammatory drugs (NSAIDs), but little is known about the mechanism. We designed two experiments to study the preventive and curative effects of hydrotalcite on NSAIDs-related gastric injury in rats and to investigate the relationship between the protective and curative mechanism of hydrotalcite and the secretion of epidermal growth factor (EGF)/prostaglandin E2 (PGE2)., Methods: Two experiments were separately designed to evaluate the preventive and curative effects of hydrotalcite. A total of 25 male rats and 25 female rats were randomly divided into five groups (vehicle group, model group, omeprazole group, hydrotalcite group, and ranitidine group) in each experiment. Rats were treated with indomethacin by gavage to build the model of acute gastric mucosal injury. The concentrations of EGF and PGE2 in blood specimens and mucosal injury indexes by gross inspection were measured and an immunohistochemical technique was also employed to test the levels of EGF, cyclooxygenase-1 (COX-1), and cyclooxygenase-2 (COX-2) in gastric mucosa., Results: Comparing with model group in both preventive and curative experiments, hydrotalcite decreased the gastric injury in the mucosa of stomach significantly (7±4.5 vs. 16±11.25, 1.5±2 vs. 2.5±6; P <0.01 , P <0.05). The levels of EGF and PGE2 in blood serum were markedly higher in hydrotalcite group than that in model group and ranitidine group in preventive experiment (574.39±34.28 vs. 486.22±41.73, 488.07±24.44; P <0.01, P <0.01). The expression levels of COX-2 in gastric mucosa were also higher in hydrotalcite group than that in model group in both preventive and therapeutic experiments (12±4 vs. 9±6, 14±7 vs. 9±4; P <0.01 , P <0.05)., Conclusions: Hydrotalcite promotes gastric protection and healing via several mechanisms, including increased levels of PGE2 in blood serum, activation of EGF, and antagonising the inhibition of cyclooxygenase (COX) caused by NSAIDs.

Objective: To detect whether muscovite exerts its protective role in the progression of atrophic gastritis (AG) and evaluate the possible mechanism., Methods: AG rats were established and then randomly divided into groups administrated with different doses of muscovite for 8 weeks. Histological changes in gastric antrum and the number of parietal cells, chief cells, and G/D cells were observed. Serum gastrin and prostaglandin E2 (PGE2) were evaluated by enzyme-linked immunosorbent assay (ELISA). The expression of proliferating cell nuclear antigen (PCNA), epidermal growth factor receptor (EGFR), C-erbB-2, p21, p53, p16 and bcl-2 in gastric tissue were detected by immunohistochemistry. The concentrations of TNF-alpha and IL-1beta secreted by THP-1 cells were detected when incubated with different doses of muscovite., Results: The grade of inflammation in muscovite groups was lower (p < 0.05), while the thickness and number of gastric glands were significantly elevated in muscovite groups (p < 0.01). The expression height of PCNA in the muscovite group was higher than in the AG group (p < 0.01). Immunohistochemistry results showed a positive expression rate of EGFR; p16 in muscovite-treated AG rats was increased (p < 0.05), while C-erbB-2 and p21 were decreased (p < 0.05). Serum gastrin and PGE2 were significantly elevated in the high-dose muscovite-treated rats (p < 0.05). In vitro studies showed that muscovite had a dose-dependent adsorption of TNF-alpha and IL-1beta., Conclusion: Muscovite could reverse gastric gland atrophy and intestinal metaplasia by promoting cell proliferation and revitalization in gastric mucosa in AG rats., (Copyright 2009 S. Karger AG, Basel.)

Objective: To explore the mucosal protective effect on the quality of gastric ulcer healing., Methods: Gastric ulcers were induced in male rats by serosal application of acetic acid. Rats were gavaged for 14 days with saline, omeprazole (OME), teprenone (TEP) and TEP plus OME starting 3 days after ulcer induction. Then the tissues and blood samples were obtained and measured., Result: The lower ulcer index (UI) and increased ulcer inhibition rate were observed in OME and OME+TEP groups. In TEP and OME+TEP groups, restored mucosa thickness increased, cystically dilated glands decreased, microvessels in connective tissue increased, the secretion of mucus, hexosamine, PGE(2), bFGF were enhanced, the expression of EGFR was increased., Conclusion: TEP can improve the quality of gastric ulcer healing, when combined with OME,the effect is more marked.

Objective: To explore the mechanisms of muscovite gastric mucosal protective effect., Method: Rat model of chronic gastritis were used. After gastric mucosal injury was induced, the rats were divided into 6 groups and were treated with different drugs. 2 weeks later, the tissue and blood samples were obtained and measured., Result: The general conditions, the observations under macroscopy, microscope and electron microscope of the middle and high dose of muscovite groups resembled those of the normal group. Their PH levels were higher than those of the model group, and the rates of intestinal metaplasia were lower, but the PGE2 level of the middle dose of muscovite group was the highest., Conclusion: Muscovite can be adsorbed on the surface of the gastric mucosa. It has gastric mucosal protective effect by improving excretion of mucus and synthesis of PGE2 in gastric mucosa, restraining gastric acid, reversing of intestinal metaplasia and decreasing inflammation cells.

Background: Long non-coding RNAs (LncRNAs) exert their functions mainly by binding to their corresponding proteins. Runt-related transcription factor 3 (Runx3) is an important transcription factor that functions as a tumor suppressor in gastric cancer. Whether there is an interplay between LncRNAs and Runx3 remains unclear.Methods: RPISeq was applied to screen the LncRNAs that potentially bind to Runx3. The interaction between LncRNA HOX antisense intergenic RNA (HOTAIR) and Runx3 was validated by RNA Immunoprecipitation and RNA pull-down assays. The role of Mex3b in the ubiquitination of Runx3 induced by HOTAIR was assessed by immunoprecipitation. Pearson’s correlation between HOTAIR mRNA expression and Runx3 protein expression was analyzed. Cell migration and invasion were explored by transwell assays.Results: We found that HOTAIR was bound to Runx3 protein and identified the fragment of HOTAIR spanning 1951-2100 bp as the specific binding site. In addition, mex-3 RNA binding family member B (Mex3b) was an E3 ligase involved in HOTAIR-induced ubiquitous degradation of Runx3. Silencing the expression of HOTAIR or Mex3b attenuated the degradation of Runx3. In human gastric cancer tissues, HOTAIR was negatively associated with the expression level of Runx3 protein (Pearson coefficient − 0.501, p = 0.025). Inhibition of HOTAIR significantly suppressed gastric cancer cell migration and invasion through upregulating claudin1, which could be reversed by co-deficiency of Runx3.Conclusions: These results uncovered the novel interaction between HOTAIR and Runx3, and provided potential therapeutic targets on the metastasis of gastric cancer. [ABSTRACT FROM AUTHOR]