·AIM: To determine the effects of laser photocoagulation on serum levels of angiopoietin-1(Ang-1),angiopoietin-2(Ang-2), soluble angiopoietin receptor Tie-2(Tie-2), Ang-1/Ang-2 ratio and vascular endothelial grow...·AIM: To determine the effects of laser photocoagulation on serum levels of angiopoietin-1(Ang-1),angiopoietin-2(Ang-2), soluble angiopoietin receptor Tie-2(Tie-2), Ang-1/Ang-2 ratio and vascular endothelial growth factor(VEGF) in patients with type 2diabetes mellitus(T2DM) and proliferative diabetic retinopathy(PDR). We also explored the role of the Ang/Tie system in PDR.·METHODS:Totally 160patientswithT2 DM, including50 patients with non-diabetic retinopathy(NDR), 58 patients with non-proliferative diabetic retinopathy(NPDR), and52 patients with PDR were enrolled in this study. Serum Ang-1, Ang-2, Tie-2 receptor and VEGF levels were measured using enzyme-linked immunosorbent assays for all patients and were repeated in 26 patients who underwent laser photocoagulation two months after the procedure.·RESULTS:ThemedianlevelsofAng-2andVEGFinserum were significantly higher in the NPDR group(4.23 ng/mL and 303.2 pg/mL, respectively) compared to the NDR group(2.67 ng/mL and 159.8 pg/mL, respectively, P 【0.01), with the highest level in the PDR group(6.26 ng/mL and531.2 pg/mL, respectively, P 【0.01). The median level of Ang-1 was significantly higher in the NPDR group(10.77ng/mL) compared to the NDR group(9.31 ng/mL) and the PDR groups(9.54 ng/mL)(P 【0.05), while no difference was observed between the PDR and NDR groups. Ang-1/Ang-2 ratio of PDR group was lowest in three groups(1.49 vs 2.69 and 2.90, both P 【0.01). The median level of Tie-2was not significantly different among three groups(P 】0.05).Ang-2 was positively correlated with VEGF and Tie-2 in the PDR and NPDR groups(both P 【0.05). Among the 26 patients who underwent laser photocoagulation, serum Ang-2 and VEGF levels significantly decreased(both P 【0.05), whereas serum Ang-1 level and Ang-1/Ang-2ratio were weakly increased(P 】0.05). The median levels of Ang-2 and VEGF in serum were highest in PDR group,however, Ang-1/Ang-2 ratio of PDR group was lowest in three groups.·CONCLUSION: Laser photocoagulation can reduce serum Ang-2 and VEGF levels. The Ang/Tie system and VEGF play an important role in the development and progression of T2 DM patients with PDR.展开更多
AIM To elucidate the underlying mechanism that microRNA-22(miR-22) promotes the apoptosis of rat pancreatic acinar cells(AR42 J) and the elements that regulate the expression of miR-22.METHODS One hundred nanomoles pe...AIM To elucidate the underlying mechanism that microRNA-22(miR-22) promotes the apoptosis of rat pancreatic acinar cells(AR42 J) and the elements that regulate the expression of miR-22.METHODS One hundred nanomoles per liter of caerulein(Cae)was administrated to induce the apoptosis of AR42 J cells and the apoptosis rate was detected by flow cytometry analysis. An amylase assay kit was used to measure the amylase expression level in the supernatant. Quantitative real-time PCR(qRT-PCR)was adopted to measure miR-22 expression. We used online tools to predict the potential transcription promoter of miR-22 and the binding sites, which was further identified by using luciferase reporter analysis,chromatin immunoprecipitation(ChIP) and ChIPqP CR assays. Then, a mimic of miR-22, Nr3 c1 plasmid encoding the glucocorticoid receptor(GR), and siNr3 c1 were used to transfect AR42 J cells, respectively.The mRNA expression of miR-22, Nr3 c1, and Erb-b2 receptor tyrosine kinase 3(ErbB3) was confirmed by qRT-PCR and the apoptosis rate of AR42 J cells was detected by flow cytometry analysis. Western blot was used to detect the expression of ErbB3, GR, PI3 k, PI3 kp85α, Akt, p-Akt, Bad, Bax, Bcl-xl, Bcl-2, and cleaved caspase3.RESULTS After inducing apoptosis of AR42 J cells in vitro, the expression of miR-22 was significantly increased by2.20 ± 0.26 and 4.19 ± 0.54 times, respectively, at3 h and 6 h in comparison with the control group.As revealed by qRT-PCR assay, the expression of miR-22 was 78.25 ± 6.61 times higher in the miR-22 mimic group relative to the miRNA control group,accompanied with an obviously increased acinar cell apoptosis rate(32.53 ± 1.15 vs 18.07 ± 0.89, P =0.0006). The upregulation of miR-22 could suppress its target gene, ErbB3, and the phosphorylation of PI3 k and Akt. Furthermore, we predicted the potential transcription promoter of miR-22 and the binding sites using online tools. Luciferase reporter analysis and sitedirected mutagenesis indicated that the binding site(GACAGCCATGTACA) of the GR, which is encoded by the Nr3 c1 gene. Downregulation of the expression of GR could upregulate the expression of miR-22, which further promoted the apoptosis of AR42 J cells.CONCLUSION GR transcriptionally represses the expression of miR-22,which further promotes the apoptosis of pancreatic acinar cells by downregulating the downstream signaling pathway.展开更多
文摘·AIM: To determine the effects of laser photocoagulation on serum levels of angiopoietin-1(Ang-1),angiopoietin-2(Ang-2), soluble angiopoietin receptor Tie-2(Tie-2), Ang-1/Ang-2 ratio and vascular endothelial growth factor(VEGF) in patients with type 2diabetes mellitus(T2DM) and proliferative diabetic retinopathy(PDR). We also explored the role of the Ang/Tie system in PDR.·METHODS:Totally 160patientswithT2 DM, including50 patients with non-diabetic retinopathy(NDR), 58 patients with non-proliferative diabetic retinopathy(NPDR), and52 patients with PDR were enrolled in this study. Serum Ang-1, Ang-2, Tie-2 receptor and VEGF levels were measured using enzyme-linked immunosorbent assays for all patients and were repeated in 26 patients who underwent laser photocoagulation two months after the procedure.·RESULTS:ThemedianlevelsofAng-2andVEGFinserum were significantly higher in the NPDR group(4.23 ng/mL and 303.2 pg/mL, respectively) compared to the NDR group(2.67 ng/mL and 159.8 pg/mL, respectively, P 【0.01), with the highest level in the PDR group(6.26 ng/mL and531.2 pg/mL, respectively, P 【0.01). The median level of Ang-1 was significantly higher in the NPDR group(10.77ng/mL) compared to the NDR group(9.31 ng/mL) and the PDR groups(9.54 ng/mL)(P 【0.05), while no difference was observed between the PDR and NDR groups. Ang-1/Ang-2 ratio of PDR group was lowest in three groups(1.49 vs 2.69 and 2.90, both P 【0.01). The median level of Tie-2was not significantly different among three groups(P 】0.05).Ang-2 was positively correlated with VEGF and Tie-2 in the PDR and NPDR groups(both P 【0.05). Among the 26 patients who underwent laser photocoagulation, serum Ang-2 and VEGF levels significantly decreased(both P 【0.05), whereas serum Ang-1 level and Ang-1/Ang-2ratio were weakly increased(P 】0.05). The median levels of Ang-2 and VEGF in serum were highest in PDR group,however, Ang-1/Ang-2 ratio of PDR group was lowest in three groups.·CONCLUSION: Laser photocoagulation can reduce serum Ang-2 and VEGF levels. The Ang/Tie system and VEGF play an important role in the development and progression of T2 DM patients with PDR.
基金National Natural Science Foundation of China,No.31671440
文摘AIM To elucidate the underlying mechanism that microRNA-22(miR-22) promotes the apoptosis of rat pancreatic acinar cells(AR42 J) and the elements that regulate the expression of miR-22.METHODS One hundred nanomoles per liter of caerulein(Cae)was administrated to induce the apoptosis of AR42 J cells and the apoptosis rate was detected by flow cytometry analysis. An amylase assay kit was used to measure the amylase expression level in the supernatant. Quantitative real-time PCR(qRT-PCR)was adopted to measure miR-22 expression. We used online tools to predict the potential transcription promoter of miR-22 and the binding sites, which was further identified by using luciferase reporter analysis,chromatin immunoprecipitation(ChIP) and ChIPqP CR assays. Then, a mimic of miR-22, Nr3 c1 plasmid encoding the glucocorticoid receptor(GR), and siNr3 c1 were used to transfect AR42 J cells, respectively.The mRNA expression of miR-22, Nr3 c1, and Erb-b2 receptor tyrosine kinase 3(ErbB3) was confirmed by qRT-PCR and the apoptosis rate of AR42 J cells was detected by flow cytometry analysis. Western blot was used to detect the expression of ErbB3, GR, PI3 k, PI3 kp85α, Akt, p-Akt, Bad, Bax, Bcl-xl, Bcl-2, and cleaved caspase3.RESULTS After inducing apoptosis of AR42 J cells in vitro, the expression of miR-22 was significantly increased by2.20 ± 0.26 and 4.19 ± 0.54 times, respectively, at3 h and 6 h in comparison with the control group.As revealed by qRT-PCR assay, the expression of miR-22 was 78.25 ± 6.61 times higher in the miR-22 mimic group relative to the miRNA control group,accompanied with an obviously increased acinar cell apoptosis rate(32.53 ± 1.15 vs 18.07 ± 0.89, P =0.0006). The upregulation of miR-22 could suppress its target gene, ErbB3, and the phosphorylation of PI3 k and Akt. Furthermore, we predicted the potential transcription promoter of miR-22 and the binding sites using online tools. Luciferase reporter analysis and sitedirected mutagenesis indicated that the binding site(GACAGCCATGTACA) of the GR, which is encoded by the Nr3 c1 gene. Downregulation of the expression of GR could upregulate the expression of miR-22, which further promoted the apoptosis of AR42 J cells.CONCLUSION GR transcriptionally represses the expression of miR-22,which further promotes the apoptosis of pancreatic acinar cells by downregulating the downstream signaling pathway.
