AIM:To investigate the effect of microRNA-429 (miR-429) on the expression of occludin (Ocln) in intestinal epithelial cells ( IECs) and intestinal epithelial barrier function in diabetic mice.METHODS:Diabetes mel-litus mouse model was induced by intraperitoneal injection of streptozocin.The expression of miR-429 in IECs of diabetic mice was inhibited by antagomiRNA-429 injected via tail vein.The expression of miR-429 and mRNA expression of Ocln were detected by real-time PCR.The protein expression of Ocln was determined by Western blotting and immunohistochem-istry.The urinary lactulose/mannitol ratio was measured by gas chromatography.The plasma LPS concentrations in the mice were measured by chromogenic end-point TAL kit.RESULTS:The results of real-time PCR confirmed that the ex-pression of miR-429 in IECs of diabetic mice was remarkably inhibited by tail-vein administration of antagomiRNA-429, and resumed to similar level of normal mice on the 6th day after the administration.After suppressing the level of miR-429, the expression of Ocln in IECs of diabetic mice increased significantly (P<0.05), while the urinary lactulose/mannitol ra-tio and the plasma LPS concentration decreased obviously ( P<0.05 ) .CONCLUSION:AntagomiRNA-429 effectively suppresses miR-429 expression in IECs of diabetic mice, and then enhances the expression of Ocln and partially resumes the intestinal epithelial barrier function.

AIM:To observe the inhibitory effect of siRNA targeting to Wip1 gene on the Wip1 gene expression in the colon cancer cells and to investigate the influence of Wip1 gene silencing on the chemotherapy sensitivity of colon cancer cells.METHODS:Wip1-811 siRNA targeting to Wip1 gene was transfected into RKO colon cancer cells with high expression of Wip1 gene.The mRNA expression of Wip1 was measured by real-time PCR.The protein level of Wip1 was detected by Western blotting.The viability of RKO colon cancer cells was measured by MTS assay.The cell apoptosis and cell cycle were analyzed by flow cytometry.RESULTS: Wip1-811 siRNA efficiently inhibited the expression of Wip1 at mRNA and protein levels.The enhanced chemotherapy sensitivity of RKO colon cancer cells was observed after inhibition of Wip1 gene expression.The viability of RKO colon cancer cells was decreased from (89.4 ±6.6)%to (74.7 ±3.9)%af-ter treated with 5-fluorouracil (P<0.05) and decreased from (77.9 ±2.4)%to (66.7 ±2.9)%after treated with oxali-platin ( P<0.05 ) .The cell apoptotic rate was increased from ( 7.7 ±0.5 )% to ( 12.3 ±3.2 )% and from ( 14.7 ± 2.1)% to (34.0 ±2.1)% when RKO colon cancer cells were treated with 5-fluorouracil and oxaliplatin, respectively (P<0.05).CONCLUSION:Wip1 gene silencing enhances chemotherapy sensitivity of colon cancer cells.