[Effects of weile powder on bicarbonate transporters CFTR SLC26A3 and SLC26A6 in gastric ulcers of rats].

OBJECTIVE: To investigate the effects of Weile Powder (WLP) on bicarbonate transporters in rats with gastric ulcers, and to probe its functional mechanisms. METHODS: The 48 SD rats were randomly divided into the normal control group, the model group, the low dose WLP group (at the daily dose of 0.075 g/mL), the middle dose WLP group (at the daily dose of 0.150 g/mL), the high dose WLP group (at the daily dose of 0.030 g/mL), and the ranitidine group (at the daily dose of 0.030 g/mL), 8 in each group. The gastric ulcer rat model was prepared by the glacial acetic acid cauterization method. Rats in each medication group were administered from the 2nd day of modeling. Rats were sacrificed after 14-day successive medication. The protein was extracted from the ulcer tissue. The protein expressions of solute carrier26A3 (SLC26A3)and solute carrier26A6 (SLC26A6) were detected using Western blot. The gastric ulcer and its peripheral tissue were sectioned. The changes of cystic fibrosis transmembrane conductance regulator (CFTR) were measured by immunofluorescence. RESULTS: Compared with the model control group, the expression levels of SLC26A3 increased in the high dose WLP group and the ranitidine group with statistical difference (P < 0.05). The expression levels of SLC26A6 increased in the high and middle dose WLP groups and the ranitidine group with statistical difference (P < 0.05). The expression level of CFTR also obviously increased in the high and middle dose WLP groups (P < 0.01). CONCLUSION: WLP could elevate the expression levels of SLC26A6, SLC26A3, and CFTR, increase the secretion of bicarbonate, thus protecting the gastric mucosa.

The molecular mechanisms of celecoxib in tumor development.

BACKGROUND: Clinical studies have shown that celecoxib can significantly inhibit the development of tumors, and basic experiments and in vitro experiments also provide a certain basis, but it is not clear how celecoxib inhibits tumor development in detail. METHODS: A literature search of all major academic databases was conducted (PubMed, China National Knowledge Internet (CNKI), Wan-fang, China Science and Technology Journal Database (VIP), including the main research on the mechanisms of celecoxib on tumors. RESULTS: Celecoxib can intervene in tumor development and reduce the formation of drug resistance through multiple molecular mechanisms. CONCLUSION: Celecoxib mainly regulates the proliferation, migration, and invasion of tumor cells by inhibiting the cyclooxygenases-2/prostaglandin E2 signal axis and thereby inhibiting the phosphorylation of nuclear factor-κ-gene binding, Akt, signal transducer and activator of transcription and the expression of matrix metalloproteinase 2 and matrix metalloproteinase 9. Meanwhile, it was found that celecoxib could promote the apoptosis of tumor cells by enhancing mitochondrial oxidation, activating mitochondrial apoptosis process, promoting endoplasmic reticulum stress process, and autophagy. Celecoxib can also reduce the occurrence of drug resistance by increasing the sensitivity of cancer cells to chemotherapy drugs.

Novel insights into ion channels in cancer stem cells (Review).

Cancer stem cells (CSCs) are immortal cells in tumor tissues that have been proposed as the driving force of tumorigenesis and tumor invasion. Previously, ion channels were revealed to contribute to cancer cell proliferation, migration and apoptosis. Recent studies have demonstrated that ion channels are present in various CSCs; however, the functions of ion channels and their mechanisms in CSCs remain unknown. The present review aimed to focus on the roles of ion channels in the regulation of CSC behavior and the CSC-like properties of cancer cells. Evaluation of the relationship between ion channels and CSCs is critically important for understanding malignancy.

Phosphatidylinositol 3-kinase is involved in prostaglandin E2-mediated murine duodenal bicarbonate secretion.

Prostaglandin E(2) (PGE(2)) plays an important role in the regulation of duodenal bicarbonate (HCO(3)(-)) secretion, but its signaling pathway(s) are not fully understood. In the present study, we investigated the signaling pathways involved in PGE(2)-mediated duodenal HCO(3)(-) secretion. Murine duodenal mucosal HCO(3)(-) secretion was examined in vitro in Ussing chambers by pH-stat titration in the presence of a variety of signal transduction modulators. Phosphatidylinositol 3-kinase (PI3K) activity was measured by immunoprecipitation of PI3K and ELISA, and Akt phosphorylation was measured by Western analysis with anti-phospho-Akt and anti-Akt antibodies. PGE(2)-stimulated duodenal HCO(3)(-) secretion was reduced by the cAMP-dependent signaling pathway inhibitors MDL-12330A and KT-5720 by 23% and 20%, respectively; the Ca(2+)-influx inhibitor verapamil by 26%; and the calmodulin antagonist W-13 by 24%; whereas the PI3K inhibitors wortmannin and LY-294002 reduced PGE(2)-stimulated HCO(3)(-) secretion by 51% and 47%, respectively. Neither the MAPK inhibitor PD-98059 nor the tyrosine kinase inhibitor genistein altered PGE(2)-stimulated HCO(3)(-) secretion. PGE(2) application caused a rapid and concentration-dependent increase in duodenal mucosal PI3K activity and Akt phosphorylation. These results demonstrated that PGE(2) activates PI3K in duodenal mucosa and stimulates duodenal HCO(3)(-) secretion via cAMP-, Ca(2+)-, and PI3K-dependent signaling pathways.