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Objective:To study the effect of thioredoxin domain containing protein 5 (TXNDC5)-peroxiredoxin 2 (Prx2) on the drug resistance of prostate cancer cells.Methods:Prostate cancer PC3 cells were cultured in vitro, treated with the chemotherapy drug cyclophosphamide (5, 10, 15 μmol/L) for 24 hours, and PC3 cells without any treatment was served as the control group. The expression levels of TXNDC5 in PC3 cells were detected by real-time fluorescent quantitative PCR (RT-qPCR) and Western blotting. PC3 cells with TXNDC5 knocking down were exposed by cyclophosphamide and CCK-8 was used to detect the cell viability of siTXNDC5 group and siNC group. The content of reactive oxygen free radicals was determined by reactive oxygen detection kit. PC3 cells and its parental cyclophosphamide-resistant ones with TXNDC5 knocking down were treated by 10 μmol/L cyclophosphamide and subjected for CCK8 assay. The expression of Prx2 in PC3 cells was detected by Western blotting after TXNDC5 was silenced. Prx2 expression was silenced in PC3 cells overexpressing TXNDC5, and cell viability and reactive oxygen free radical content were detected in Vec-Ctrl group, pcTXNDC5 group, siNC group, siPrx2 group and pcTXNDC5+ siPrx2 group. Results:Compared with the control group, cyclophosphamide treatment significantly increased the expression of TXNDC5 at mRNA and protein levels in PC3 cells. After PC3 cells were treated with cyclophosphamide (10, 15 μmol/L) for 12 h, compared with the siNC group, the cell viability in the siTXNDC5 group was significantly suppressed (0.44±0.08 vs. 0.74±0.10, t=3.647, P=0.031; 0.30±0.04 vs. 0.53±0.06, t=6.115, P=0.006). When PC3 cells were treated with 10 μmol/L cyclophosphamide for 6 and 12 h, compared with the siNC group, the production of reactive oxygen free radicals in the siTXNDC5 group was significantly increased (2.68±0.19 vs. 1.58±0.26, t=-6.027, P=0.005; 4.56±0.37 vs. 2.73±0.26, t=-6.995, P=0.003). When PC3 cells and its cyclophosphamide-resistant ones were treated with 10 μmol/L cyclophosphamide for 12 h, compared with the siNC group, the cell viability was significantly inhibited in the siTXNDC5 group. Western blotting analysis showed that the expression of Prx2 was significantly reduced when TXNDC5 was silenced. Silencing Prx2 could significantly attenuate the increase of cell viability and the decrease of reactive oxygen content resulting from TXNDC5 overexpression. PC3 cells were treated with 10 μmol/L cyclophosphamide for 12 h, and the cell viabilities of the Vec-Ctrl group, pcTXNDC5 group, siNC group, siPrx2 group and pcTXNDC5+ siPrx2 group were 0.52±0.07, 0.69±0.03, 0.56±0.05, 0.43±0.05, 0.58±0.07, respectively, and there was a statistically significant difference ( F=8.868, P=0.003). Furthermore, the cell viability in the pcTXNDC5+ siPrx2 group decreased significantly when compared to that of the pcTXNDC5 group ( P=0.045). The contents of reactive oxygen free radicals in the above 5 groups were 3.26±0.46, 2.09±0.49, 3.16±0.38, 4.62±0.26, 2.87±0.36, respectively, and there was a statistically significant difference ( F=16.037, P<0.001). The content of reactive oxygen radicals in the pcTXNDC5+ siPrx2 group was higher than that of the pcTXNDC5 group ( P=0.036). Conclusion:TXNDC5 can reduce the level of reactive oxygen free radicals in prostate cancer cells by regulating the expression of Prx2, so as to promote the drug resistance of prostate cancer cells.
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Objective@#To investigate the effect of peroxiredoxin 2 (Prx2) overexpression on fibroblast proliferation and collagen synthesis induced by transforming growth factor-β1 (TGF-β1) .@*Methods@#Fibroblasts were randomly divided into control group (DMEM medium) , TGF-β1 group (5 μg/L TGF-β1) , negative control group (treated with 5 μg/L TGF-β1 and transfected with empty lentiviral vector) , and Prx2 group (treated with 5 μg/L TGF-β1 and transfected with Prx2 overexpression lentiviral vector) . MTT assay was used to measure cell proliferation, immunofluorescence assay was used to measure the expression of 8-OHdG, and Western blot was used to measure the expression of p-JNK, p-P38, collagen type I, collagen type III, and Prx2. SPSS 18.0 was used for statistical analysis. The continuous data were expressed as mean±standard deviation; an analysis of variance was used for comparison between groups, and the least significant difference t-test was used for further comparison between two groups.@*Results@#Lentiviral transfection was performed successfully, and the Prx2 group had a significant increase in the protein expression of Prx2 (P<0.05) . Compared with the control group, the TGF-β1 group had a significant increase in the proliferation ability (P<0.05) , and compared with the TGF-β1 group, the Prx2 group had a significant reduction in the proliferation ability (P<0.05) . Compared with the control group, the TGF-β1 group had significant increases in the expression of 8-OHdG, p-JNK, p-P38, collagen type I, and collagen type III (P<0.05) ; compared with the TGF-β1 group, the negative control group had no significant changes in the expression of 8-OHdG, p-JNK, p-P38, collagen type I, and collagen type III (P>0.05) , while the Prx2 group had significant reductions in the above parameters (P<0.05) .@*Conclusion@#Prx2 overexpression inhibits fibroblast proliferation and collagen synthesis induced by TGF-β1 through inhibiting reactive oxygen species and activating the JNK and P38 pathways.
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Objective The molecular mechanisms underlying sperm DNA damage remain uncertain. This study aimed to determine the expression difference of Prdx2 protein between normal and damaged sperm DNA,and analyze the correlation between expression of Prdx2 protein in human mature spermatozoa and sperm DNA damage．Methods Semen specimens of sixty-seven male infertility patients were collected．They were separated in three groups according to the sperm DNA damage levels: normal group， slight damage group，and severe damage group．Total protein of human of mature spermatozoa was extracted．The expression of Prdx2 protein was detected by western blotting．The Localization of Prdx2 in spermatozoa was detected by immunofluorescence.Results Comparing the expression of Prdx2 protein with group normal(9.06±1.80), group slight damage(6.32±1.89） and group severe damage（2.87±0.83） decreased by 30.2% and 68.2% respectively (P<0.01).Immunofluorescence showed that Prdx2 was mainly distributed in the mitochondria and nuclear of spermatozoa.Immunofluorescence Results showed that Prdx2 was mainly located in the mitochondria of human sperm midsection and the nucleus region of the sperm head. The expression of Prdx2 in both group slight damage and group severe damage was lower than that in the group normal.The positive Prdx2 response was significantly reduced in group severe damage.The protein expression of Prdx2 was negatively correlated with DFI(r=-0.478,P<0.01), and was positively correlated with progressive motility and total motility(r=0.135、0.128，P<0.01).Conclusion Human sperm Prdx2 protein expression may be involved in protecting sperm DNA and affecting sperm motility by maintaining intracellular redox balance.
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Objective To investigate the neuroprotective effect and mechanism of liraglutide on diabetic rats. Methods 24 healthy male SPF Goto-Kakizaki (GK) rats with random blood glucose greater than 11.1 mmol/L were selected as the experimental group, and randomly divided into diabetes mellitus group ( n＝12) and liraglutide group (n＝12). Ten healthy male SPF Wistar rats with the same age and weight as GK rats were selected as normal control group. After adaptively feeded for 2 weeks, the liraglutide group was given liraglutide (400 μg·kg－1·d－1, subcutaneous injection), while the control group and diabetes mellitus group were given the same volume of saline, and continued to be administered for 8 weeks. After 10 weeks, data and biochemical indicators were recorded. Effects of liraglutide on learning and memory in diabetes mellitus rats were detected by Morris water maze test. HE staining observed the hippocampal neurons morphology. Western blotting method detected the expression of p- IκB kinase (IKK) β, p-NF-κB, NF-κB, Klotho, and PRX2 in hippocampus. Results Morris water maze test showed that liraglutide can improve the spatial learning and memory ability of diabetes mellitus rats. HE staining showed that liraglutide significantly reduced the pathological damage of hippocampal neurons of diabetes mellitus rats. Western blotting showed that liraglutide inhibited NF-κB signaling pathway in hippocampus of diabetes mellitus rats. The expression of Klotho protein in hippocampus of diabetes mellitus group was significantly lower than that of control group, while the expression of PRX2 protein was higher than control group (t＝8.298,－7.398,all P<0.01). The expression of Klotho and PRX2 protein in hippocampus of liraglutide group were higher than diabetes mellitus group (t＝－13.059, 14.113, all P<0.01). The expression of Klotho protein of liraglutide group was similar to that of control group ( t ＝ －1. 137, P>0. 05 ). The expression of PRX2 protein was significantly higher than control group (t＝－28.055, P<0.01). Conclusions Liraglutide may enhance the expression of antioxidant stress protein including Klotho and PRX2, by inhibiting NF-κB signaling pathway in hippocampus of diabetes mellitus rats, reduced oxidative stress and improved the injury of hippocampal neuronal in diabetes mellitus rats, which seems to play a neuroprotective effect, to prevent and delay the occurrence of diabetic encephalopathy.
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Objective To explore the effects of the down-regulating peroxiredoxin 2 (PRDX2) on invasion, migration and proliferation of human gastric cancer MGC803 cells by using RNA interference. Methods MGC803 cells were divided into 3 groups:blank control group,negative control group and PRDX2 siRNA group. Transwell assay was used to examine the invasive ability change of MGC803 cells after transfection. Scratch test was used to detect the change of MGC803 cells migration ability after transfection. Western blot was used to examine the expression changes of PRDX2, matrix metalloproteinase (MMP)-2 and MMP-9. The proliferation ability of MGC803 cells was assessed by using CCK-8 assay. Results The expressions of PRDX2(0.345±0.006,0.721±0.013,0.720±0.014),MMP-2(0.067±0.012, 0.391±0.015, 0.371± 0.016) and MMP-9 (0.073±0.013, 0.341±0.028, 0.346±0.024) in the PRDX2 siRNA group were lower than those in the blank control group and negative control group (all P < 0.05). The cell invasion, migration and proliferation were inhibited in MGC803 cells (all P < 0.05). Conclusion PRDX2 is overexpressed in MGC803 cells. Down-regulating the expression of PRDX2 could inhibit the invasion, migration and proliferation of MGC803 cells.
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Diabetes is a major risk factor for stroke and is also associated with worsened outcomes following a stroke. Peroxiredoxin-2 exerts potent neuroprotective effects against oxidative stress. In the present study, we identified altered peroxiredoxin-2 expression in an ischemic stroke model under hyperglycemic conditions. Adult male rats were administrated streptozotocin (40 mg/kg) via intraperitoneal injection to induce diabetes. Middle cerebral artery occlusion (MCAO) was induced surgically 4 weeks after streptozotocin treatment and cerebral cortex tissues were isolated 24 hours after MCAO. Peroxiredoxin-2 expression was evaluated in the cerebral cortex of MCAO-operated animals using a proteomics approach, and was found to be decreased. In addition, the reduction in peroxiredoxin-2 levels was more severe in cerebral ischemia with diabetes compared to animals without diabetes. Reverse-transcriptase PCR and Western blot analyses confirmed the significantly reduced peroxiredoxin-2 expression in MCAO-operated animals under hyperglycemic conditions. It is an accepted fact that peroxiredoxin-2 has antioxidative activity against ischemic injury. Thus, the findings of this study suggest that a more severe reduction in peroxiredoxin-2 under hyperglycemic conditions leads to worsened brain damage during cerebral ischemia with diabetes.
Subject(s)
Adult , Animals , Humans , Male , Rats , Blotting, Western , Brain , Brain Ischemia , Cerebral Cortex , Hyperglycemia , Infarction, Middle Cerebral Artery , Injections, Intraperitoneal , Middle Cerebral Artery , Neuroprotective Agents , Oxidative Stress , Polymerase Chain Reaction , Proteomics , Risk Factors , Streptozocin , StrokeABSTRACT
Objective To construct a lentiviral expression vector of peroxiredoxin2(PRDX2) RNA interference (RNAi) and to investigate the effect of siRNA of PRDX2 genes on the proliferation of human colonrectal cancer SW480 cell .Methods RNAi tar‐get sequences were designed and synthesized towards the PRDX2 gene sequences .The lentiviral vector pGC‐EGFP‐shPRDX2 was constructed and identified .The vector was transformed into SW480 cells ,and the transfection efficiency was evaluated by fluores‐cence microscopy .The expression of PRDX2 was detected with Quantitative real‐time PCR (qRT‐PCR) and Western blot in the transfected cells .Cell growth and colony forming ability were detected with MTT and plate cloning technique .Results PRDX2 gene lentiviral vector was successfully established and was proved by gene sequencing .The expression of PRDX2 in mRNA and pro‐tein was significantly reduced(P<0 .05) .The PRDX2 mRNA and protein expression in SW480 transfected with lentiviral were sig‐nificantly reduced (P< 0 .05) ,and the ability of growth and proliferation were significantly reduced(P< 0 .05) .Conclusion PRDX2 gene lentiviral vector could be a stable and reliable tool .The proliferation and growth of SW480 cells transfected by pGC‐EGFP‐shPRDX2 could be effectively suppressed ,which could facilitate further investigation of the roles of PRDX2 gene in the de‐velopment and progression of colorectal cancer .
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To construct the lentiviral vector containing Peroxiredoxin 2(Prdx2) gene and the colorectal cancer cell line stably transduced with Prdx 2-containing vector , so as to provide a useful tool for studying the role of Prdx 2 in colorectal cancer.Methods: Prdx2 was amplified by PCR and inserted into lentiviral expression vector Ubi-MCS-EGFP-IRES-Puromycin (GV218) to generate Ubi-Prdx2-EGFP-Puromycin(LV-Prdx2) vector.The inserted Prdx2 gene was verified by double enzyme digestion and DNA sequencing.Subsequently ,lentiviruses were produced and transduced into SW 480 cells.EGFP expression was examined under fluorescence microscopy ,the expression of Prdx2 was detected with qRT-PCR and Western blot.Cell growth and colony forming ability were detected with MTT and plate cloning technique.Results: The lentiviral Prdx2 expression vector was successful construc-ted.Overexpression of Prdx2 was verified in SW480 cells with LV-Prdx2 vector.Prdx2 promoted SW480 cell growth and colony forming ability(P<0.05).Conclusion:Ubi-Prdx2-EGFP-Puromycin(LV-Prdx2) vector is successfully constructed,and the SW480/LV-Prdx2 cell line with stable transduction of Prdx2 containing vector is established.Overexpression Prdx2 can significantly promote the proliferation of colorectal cancer SW 480 cells.