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Background and Objectives@#miR-450a-5p was involved in fat formation, however, its role in insulin resistance remains unclear. This study investigated the effects of miR-450a-5p on endothelial cells, with the aim of finding a potential target for diabetes mellitus. @*Methods@#and Results: Human umbilical vein endothelial cells (HUVECs) were treated with low-glucose, high-glucose, methylglyoxal (MGO), and insulin alone or in combination with MGO. The expression of miR-450a-5p in treated cells was measured by quantitative real-time polymerase chain reaction (qRT-PCR) assays. The cell activity, migration and fat formation were determined by MTT experiments, Transwell assay and oil red O staining. The expressions of eNOS/ AKT pathway-related proteins in cells were assessed by Western blot (WB) analysis. Furthermore, the target gene of miR-450a-5p was analyzed by double-luciferase reporter analysis, and its effects on eNOS/AKT pathway were estimated. We found that the expression of miR-450a-5p was decreased obviously in endothelial cells treated with high-glucose and MGO. In vitro cell experiments showed that MGO could not only promote the activity of endothelial cells, but also accelerate cell migration and fat accumulation, which, however, could be reversed by up-regulation of miR-450a-5p. Moreover, MGO inhibited eNOS/AKT pathway activation and NO release mediated by insulin, and such effects were reversed by up-regulation of miR-450a-5p. Furthermore, CREB was the target gene for miR-450a-5p, had an activation effect on the eNOS/AKT pathway. @*Conclusions@#Up-regulated miR-450a-5p eliminates MGO-induced insulin resistance via targeting CREB, and therefore could be used as a potential target to improve insulin resistance and treat patients with diabetes-related diseases.
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Objective To investigate the expression of Bcl-2,survivin and pancreatic cancer stem cells markers Oct-4 and ABCG2 in pancreatic cancer cells resistance to chemoradiotherapy.and explore its mechanism.Methods Concurrent ehemoradiotherapy was used to obtain pancreatic cancer cells resistant to chemoradiotherapy,the pancreatic cancer cells without chemoradiotherapy treatment were used as control.Western-blot was applied to detect the expression of Bcl-2,survivin,Oct-4,ABCG2.Results The expression of Bcl-2 was 0.7955±0.0326,0.5718±0.0212,0.6137±0.0382 and 0.8733±0.0461,respectively;the expression of survivin protein was 0.8207±0.0490,0.6973±0.0211,0.7967±0.0346 and 0.8013±0.0398,respectively;the expression of Oct-4 protein was 0.8728±0.0177,0.7861±0.0139,0.4794±0.0932 and 0.4216±0.1043,respectively;the expression of ABCG2 protein was 0.7810±0.1370,0.4957±0.1126,0.6102±0.1358 and 0.4670±0.1274,respectively.in resistant pancreatic cancer cells of SW1990,BxPC3,pc3,jf305 cell line.The corresponding values in the control group were 0.4723±0.018,0.2954±0.0103.0.3587±0.0201 and 0.2718±0.0136;0.4717±0.0274,0.3587±0.0113,0.3891±0.0147 and 0.3326±0.0124;0.6053±0.0142,0.4236±0.0086.0.2385±0.0671 and 0.1985±0.0582;0.3156±0.0582.0.2360±0.0423,0.2813±0.0512 and 0.1808±0.a0370.The expression of all the four proteins significantly increased after ehemoradiotherapy(P＜0.05).Conclusions Pancreatic cancer cells resistant to chemoradiotherapy may contain cancer stem cells.