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@#Objective To investigate the protective effect of insulin-like growth factor-1 (IGF-1) on 6-hydroxy dopamine (6-OHDA) induced oxidative damage in PC-12 cells. Methods PC12 cells were treated with 6-OHDA (concentrations of 25, 50, 100, 150 and 200 μmol/L). In order to select the optimal experimental concentration and treatment time, the activity of PC12 cells was detected by MTT at different time points of 12 h, 24 h and 48 h after treatment. PC12 cells were divided into three groups: control group, 6-OHDA group and IGF-1+6-OHDA group. The activity of PC12 cells was detected by MTT assay. Reactive oxygen species (ROS) level of PC12 cells was detected by immunofluorescence staining, and apoptosis was detected by Hoechst33342 / PI double staining method. Results With the increased concentration and the prolongation of the action time of 6-OHDA, the activity of PC12 cells decreased gradually. The concentration of 150 μmol/L and action time of 24 h of 6-OHDA were selected as the optimal experimental concentration and observation time for this study. Compared with 6-OHDA group, the activity of PC12 cells increased, the expression level of ROS and the apoptosis decreased in IGF-1+6-OHDA group. Conclusion IGF-1 pretreatment can reduce 6-OHDA induced oxidative damage and apoptosis of PC12 cells, also can increase cell activity, which can provide a potential strategy for the prevention and treatment of Parkinson’s disease.
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[Objective]To investigate the expression changes of miR-133b in methamphetamine(MA)-induced neuro-nal injury in PC12 cells and its regulative effects on cellular apoptosis.[Methods]PC12 cells were cultured and divided into control group and MA treated group.In MA treated group,PC12 cells were insulted with 800μmol/L MA in culture medium. The cellular injury of PC12 cells was observed under microscope. The cellular apoptosis was detected by Hoechst33342/PI double staining,and the expression level of miR-133b was examined by real-time quantitative PCR(RT-PCR). Further-more,miR-133b mimic and inhibitors were transfected into PC12 cells to analyze miR-133b's function in MA-induced cell apoptosis.[Results]The data showed that 800 μmol/L MA could induce obvious cellular injury,cause neurite shortened and increase the cell apoptosis. The RT-PCR data showed that the expression of miR-133b of PC12 cells treated with MA de-creased significantly.The apoptosis rate of PC12 cells decreased after transfection of miR-133b mimic,while increased after transfection of miR-133b inhibitors.[Conclusions]High concentration of MA causes neuron damage and induces neuronal apoptosis,and also decreases the levels of miR-133b expression. Whereas,overexpression of miR-133b can reduce the apoptosis of cultured PC12 cells.Thus,miR-133b plays a crucial role in MA mediated neurotoxicity.This study provides a theoretical basis for elucidating the mechanism of MA-induced neurotoxicity and may provide a new strategy for treating MA addiction.
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Background Vitronectin is a glycoprotein that has a variety of functions.Its expression was markedly higher in the retina of oxygen induced mice,which was confirmed in our animal model,and also increased in human umbilical vein endothelial cells (人 UVECs) that were cultured in high glucose.However,there was no evidence that showed vitronectin was involved in retinal neovascularization.Objective This study was to observe the influence of vitronectin on cytoskeleton remodeling,cell migration and blood vessel formation in 人 UVECs conditioned by high glucose.Methods 人 UVECs were cultured in high glucose and the expression of vitronectin was knocked down using RNA interference technology.The experiments were divided into the high glucose group (人 UVECs were conditioned with DMEM medium that contained 50 mmol/L glucose),negative interference group (人 UVECs were transfected with control siRNA in advance,and then were conditioned with DMEM medium that contained 50 mmol/L glucose) and positive interference group (HUVEC were transfected with vitronectin siRNA in advance,and then were conditioned with DMEM medium that contained 50 mmol/L glucose).The protein expression of vitronectin was measured by Western blot,and the microfilament cytoskeleton of 人 UVECs was examined by immunofluorescence cytochemical staining followed by fluorescence microscopy.Cell migration ability in a scratch wound assay and blood vessel formation ability in a matrigel assay of 人 UVECs were evaluated.The general differences were analysed by One-Way ANOVA ;further contrasts of the two groups were analysed by the LSD-t test.Results The differences in vitronectin expression of the three groups were not obvious at 0 hour (F=1.064,P＞0.05).After 24 hours,vitronectin expression was highest in the high glucose group,lower in the negative interference group,and the lowest in the positive interference group,and the differences were significant (F =15.519,P＜0.05).After 48 hours,vitronectin expression of the three groups displayed the same pattern,and the differences were also significant (F=37.521,P＜0.05).Immunofluorescence showed that the cytoskeleton structure was most obvious in the high glucose group,moderate in the negative interference group,and was the least obvious in the positive interference group,after both 24 hours and 48 hours.In the scratch wound assay,the cell migration ability of the high glucose group was the highest,lower in the negative interference group,and the lowest in the positive interference group after 24 hours,and the differences were significant (F=90.685,P＜0.05).After 48 hours,the cell migration abilities of the three groups displayed the same pattern,and the differences were also significant (F=67.880,P＜0.05).In the matrigel assay,after 6 hours,the number of blood vessels formed in the high glucose group was more than that in the negative interference group,and the least amount was found in the positive interference group.The differences among of them were significant (F =86.653,P＜0.05).The number of blood vessel formed in the positive interference group was also the lowest after 12 hours,and the differences were also significant (F=18.992,P＜0.05).Conclusions Vitronectin can bring about cytoskeleton remodeling,increase in cell migration,and enhancement of blood vessel formation in 人 UVECs conditioned in high glucose.It may be one of the important influence factors of diabetic retinopathy.
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Background Researches determined that the alteration of A69S locus of age-related maculopathy susceptibility 2 ( ARMS2 ) gene is closely associated with the pathogenesis and progression of age-related maculopathy ( AM D ).However,the location of ARMS2 protein in normal eye tissue is still in controversy,therefore,its function is below understanding up to now.Objective The goal of this laboratory work was to investigate the distribution,expression and location of ARMS2 protein in normal adult retina and choroid as well as in retinal pigment epithelial (RPE) cells and lay a basis for exploring further its function in the protein level.Methods Ten donor eyeballs of normal adult male with the age from 28-42 years were collected in eye bank of Qingdao Eye Hospital.The frozen sections of the retina and choroid were prepared for the detection and location of ARMS2 in 3 eyes by immunofluorescence under the confocal laser microscope.The retina was isolated for the primary culture of RPE cells using explant culture method.The cells were then identified by CK32 antibody by immunofluorescence.The distribution and expression of the ARMS2 protein in retina,ehoroid and RPE cells were determined by immunofluorescence technique.Results ARMS2 protein was strongly expressed in retinal vessel,RPE cell layer,Bruch membrane and choroidal vessel,but weak expression was in retinal ganglion cell layer,inner nuclear layer,outer plexiform layer,outer nuclear layer and inner plexiform layer in the normal eyes.The primarily cultured cells appeared the polygon shape with the abundant pigment in cytoplasm.The immunofluorescence of the cells showed the positive response for CK32,exhibiting the green fluorescence granules in the cytoplasm.The positive expression of ARMS2 protein also was seen in the cytoplasm of RPE cells,appearing the red fluorescence.Conclusions ARMS2 protein mainly distribute and locate retinal and choroidal vessels,RPE cells and Bruch membrane in normal eye.