Protective effect of small interfering RNA targeting HIF-1α in retina of diabetic retinopathy mice and its mechanism / 国际眼科杂志(Guoji Yanke Zazhi)

@#AIM: To investigate the protective effect of small interfering RNA targeting HIF-1α in retina of diabetic retinopathy mice and its mechanism. <p>METHODS: Totally 40 C57BL/6 male mice were randomly divided into the normal group, diabetes group, siRNA-HIF-1α group and siRNA-NC group. The diabetic models were constructed. The histopathological change of the retina of the mice was observed in each group. The microvessel density(MVD)was detected by immunohistochemistry. The expressions of HIF-1α, VEGF,NF-κB, IL-1, IL-6 and TNF-α mRNA in the retina in each group were detected by real-time quantitative PCR. The expressions of HIF-1α, ET-1 and vWF proteins in the retina in each group were detected by Western blot. <p>RESULTS: The body weights of diabetes group, siRNA-NC group and siRNA-HIF-1α group were lower than the normal group, while the blood glucose levels were higher than the normal group(All <i>P</i><0.05). The MVD in the diabetic group and siRNA-NC group were significantly higher than those in the normal group, while the siRNA-HIF-1α group were significantly lower than the diabetes group and siRNA-NC group(All <i>P</i><0.05). Compared with the diabetes group and siRNA-NC group, the relative expression levels of HIF-1α, VEGF, NF-κB, IL-1, IL-6 and TNF-α mRNA in the retina in the siRNA-HIF-1α group were decreased(All <i>P</i><0.05). Compared with the diabetes group and siRNA-NC group, the relative expression levels of HIF-1α,ET-1 and vWF proteins in the retina in the siRNA-HIF-1α group were decreased(All <i>P</i><0.05).<p>CONCLUSION: Specific silencing of HIF-1α gene could protect the retina of DR. The mechanism may be related to the reduction of angiogenesis and vascular endothelial injury.

Targeting of integrin-linked kinase with a small interfering RNA inhibits human penile smooth muscle cell contraction and stretch in vitro / 中华泌尿外科杂志

Objective To investigate the changes of human penile smooth muscle cell contraction and stretch resulting from the integrin-linked kinase (ILK) gene knock-down.Methods Cultured human penile smooth muscle cells were knocked down for ILK using a small interfering RNA (SiRNA).Cellular ILK expression was quantified by Western blot analysis.Cell attachment,spreading and migration were also performed.Furthermore,microfilament dynamics was tested by means of Alexa Fluor 488 phalloidin stain.Results First,blocking the expression of ILK by siRNA significantly inhibited human penile smooth muscle cell attachment,speading and migration; moreover,ILK down-regulation affected actin cytoskeleton reorganization and changed cell morphology in human penile smooth muscle cell.Conclusions Targeting of ILK with a small interfering RNA not only inhibits human penile smooth muscle cell attachment,spreading and migration,but also effectively suppresses microfilament dynamics.This may be of potential therapeutic usefulness in treating erectile dysfunction (ED).

Par-4 gene silence inhibited hydrogen peroxide-induced apoptosis in alveolar epithelial cells / 中华急诊医学杂志

Objective To investigate the effects of Par-4 gene silence on hydrogen peroxide-induced apoptosis in alveolar epithelial cells. Method The alveolar epithelial cells A549 were cultured and exposed to hydrogen peroxide. The siRNA sequences targeted Par-4 gene was chemically synthesized and transfected to A549 cells with or without the exposure of hydrogen peroxide. The cells were divided into normal control groups, hydrogen peroxide-treated group(The cells were treated with 0. 1 mmol/L hydrogen peroxide), hydrogen peroxide and Par-4-siRNA-treated group(The cells were treated with 0. 1 mmol/L hydrogen peroxide after transfection of Par-4-siRNA), Non-specific DNA sequence transfection control group. The apoptosis of A549 cells was quantified by flow cytometry. The expression of Smac protein was detected by Western blot.Electrophoretic mobility shift assay was applied for evaluating the change of E2F1 DNA binding activity. Relative activity of Caspase-3 was detected by clolorimetric assay. Results The percent of apoptotic cells in hydrogen peroxide and Par-4-siRNA-treated group was (29.7 ± 2.3) %, which was significantly lower than that of hydrogen peroxide-treated group [(54.2 ± 4.1)%, q= 8.91, P ＜ 0.01)]. Par-4 siRNA could significantly suppress the increase of Smac protein, E2F1 DNA binding activity and caspase-3 activity induced by hydrogen peroxide in A549 cells. Conclusions Par-4 gene silence induced by siRNA might inhibit the apoptosis of alveolar epithelial cells, which might be resulted from suppression of the up-regulation of Smac gene expression, E2F1 DNA binding activity and caspase-3 activity.