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AIM: To investigate the mechanism of pyrrolidine dithiocarbamate(PDTC)on transforming growth factor-beta 2(TGF-β2)-induced epithelial-mesenchymal transition(EMT)in human lens epithelial cells(LECs).METHODS: LECs were treated with various doses of PDTC chemicals following TGF-β2 caused EMT on these cells. Cell proliferation and lateral migration were discovered using the CCK-8 and cell scratch test. The markers of EMT, including E-cadherin, α-SMA and nuclear factor-κB(NF-κB)signaling pathway-related expression, were tested by Western Blot as well as the changes in the expression of the apoptosis-related proteins BAX, BCL-2, Caspase-3, and Cyclin D1.RESULTS: The proliferation and migration viability of cells in the TGF-β2 treated group was increased compared to the group without TGF-β2, and the expression of α-SMA increased whereas the E-cadherin expression decreased. With the effect of TGF-β2, NF-κB p65 and phosphorylated NF-κB p65 expression increased, the concentration of TGF-β2 that had the greatest capacity for proliferation and migration was 10 ng/mL(P<0.05). Mechanism study of PDTC-induced EMT reversal and apoptosis showed that cell viability and migratory capability were both significantly reduced after PDTC intervention; PDTC prevents IκB phosphorylation, thus inhibiting NF-κB nuclear translocation. Protein associated to the NF-κB signaling pathway, and protein expression of NF-κB/IκBα/p-IκBα/Iκκ-α/p-Iκκ-α was decreased(P<0.05), PDTC increased the expression of the pro-apoptotic protein BAX/Caspase-3, expression of the inhibitor of apoptosis protein BCL-2 and the cell cycle protein Cyclin D1 was reduced. The expression of NF-κB/IκB mRNA was reduced, expression of the apoptosis-related mRNA BAX increased, while BCL-2 reduced.CONCLUSION: The EMT in LECs cells induced by TGF-β2 can be significantly reversed by PDTC, which may be related to the decreased expression of NF-κB p65/IκB/Iκκ-α and activation of apoptosis-related protein. PDTC can reverse EMT by inhibiting NF-κB signaling pathway and induce apoptosis of abnormally proliferated cells, which will provide new potential therapeutic agents for posterior capsular opacification(PCO)treatment.
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Objective:To investigate the regulatory effect of astaxanthin on oxidative stress injury induced by hydrogen peroxide (H 2O 2) in lens epithelial cells and its possible mechanism. Methods:The HLEB-3 cells were cultured with different concentrations (0, 50, 100, 200, 500, 750 μmol/L) of H 2O 2.The cell inhibition rate was detected by the methyl thiazolyl tetrazolium (MTT) method, and the 50%inhibiting concentration (IC50) was calculated.HLEB-3 cells were cultured with different concentrations (0, 5, 10, 20, 50 μmol/L) of astaxanthin.The cell survival rate was detected by the MTT method.HLEB-3 cells were divided into four groups for 24-hour culture, namely normal control group cultured with complete medium, oxidative stress group cultured with 250 μmol/L H 2O 2, 10 μmol/L astaxanthin group cultured with 10 μmol/L astaxanthin and 250 μmol/L H 2O 2, and 20 μmol/L astaxanthin group cultured with 20 μmol/L astaxanthin and 250 μmol/L H 2O 2.The cell apoptosis rate was determined by flow cytometry.The nitric oxide (NO) concentration, superoxide dismutase (SOD) activity, glutathione (GSH) activity and malondialdehyde (MDA) content were detected by ELISA.The protein expressions of nuclear factor erythroid-2 related factor 2 (Nrf2) in nuclei, cytoplasmic Nrf2, heme oxygenase-1 (HO-1) and NAD (P) H, quinine oxidoreductase 1 (NQO1) were detected by Western bolt.The cells were divided into four groups, namely normal control-small interfering RNA (NC-siRNA) group, Nrf2-siRNA group, NC-siRNA+ astaxanthin group and Nrf2-siRNA+ astaxanthin group.The cells were transfected with NC-siRNA or Nrf2-siRNA accordingly.The cells were co-cultured for 24 hours with 0/10 μmol/L astaxanthin and 250 μmol/L H 2O 2 24 hours after transfection, respectively.The cell apoptosis rate was determined by flow cytometry.The NO concentration, SOD activity, GSH activity and MDA content were detected by ELISA. Results:With the increase of H 2O 2 concentration, the inhibition rate of HLEB-3 cells increased.There were significant differences in the inhibition rate of HLEB-3 cells treated with different concentrations of H 2O 2 ( F=12.358, P<0.05). The IC50 value of H 2O 2 on HLEB-3 cells was 264.20 μmol/L.The survival rates of HLEB-3 cells treated with 0, 5, 10, 20 and 50 μmol/L astaxanthin were (100.00±0.00)%, (102.20±1.34)%, (109.50±3.60)%, (115.40±4.13)%, (93.60±2.59)%, respectively.Then 10 μmol/L and 20 μmol/L were chosen as the experimental dose.The cell apoptosis rate of oxidative stress group was (38.50±2.38)%, which was higher than (9.20±0.24)% of normal control group, with a statistically significant difference ( P<0.05). The cell apoptosis rate of 10 μmol/L astaxanthin group was (27.60±4.33)%, which was lower than (38.50±2.38)% of oxidative stress group, but higher than (14.90±1.23)% of 20 μmol/L astaxanthin group and (9.20±0.24)% of normal control group, showing statistically significant differences (all at P<0.05). The NO and MDA contents were higher and the SOD and GSH concentrations were lower in oxidative stress group than in normal control group, 10 μmol/L astaxanthin group and 20 μmol/L astaxanthin group, and the differences were statistically significant (all at P<0.05). The NO and MDA contents were higher and the SOD and GSH concentrations were lower in 10 μmol/L astaxanthin group than in normal control group and 20 μmol/L astaxanthin groups, and the differences were statistically significant (all at P<0.05). There were significant differences in the relative expression levels of nuclear Nrf2, cytoplasmic Nrf2, HO-1 and NQO1 proteins among normal control group, oxidative stress group, 10 μmol/L astaxanthin group and 20 μmol/L astaxanthin group ( F=43.512, 20.381, 31.014, 23.435; all at P<0.001). The relative expression of nuclear Nrf2 protein gradually decreased, and the relative expression of nuclear Nrf2, HO-1 and NQO1 proteins increased gradually in normal control group, oxidative stress group, 10 μmol/L astaxanthin group and 20 μmol/L astaxanthin group, and there were significant differences when compared in pairs (all at P<0.05). The apoptosis rates of Nrf2-siRNA group and Nrf2-siRNA+ astaxanthin group were higher than those of NC-siRNA group and NC-siRNA+ astaxanthin group, and the differences were statistically significant (all at P<0.05). The cell apoptosis rate was higher in NC-siRNA group than in NC-siRNA+ astaxanthin group, showing a statistically significant difference ( P<0.05). There was no significant difference in the apoptosis rate between Nrf2-siRNA+ astaxanthin group and Nrf2-siRNA group ( P>0.05). The NO and MDA concentrations were higher and the SOD and GSH activities were lower in Nrf2-siRNA group than in the NC-siRNA group, with statistically significant differences (all at P<0.05). The NO and MDA concentrations were lower and the SOD and GSH activities were higher in NC-siRNA+ astaxanthin group than in NC-siRNA group and Nrf2-siRNA+ astaxanthin group, and the differences were statistically significant (all at P<0.05). There was no significant difference in NO and MDA concentrations or the SOD and GSH activities between Nrf2-siRNA+ astaxanthin group and Nrf2-siRNA group (all at P>0.05). Conclusions:Astaxanthin enhances the resistance of lens epithelial cells to H 2O 2-induced oxidative stress damage, which may be achieved by activating the Nrf2-related signaling pathway.
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AIM: To scrutinize the role of the Wnt/β-catenin signaling pathway in the epithelial-mesenchymal transition(EMT)of lens epithelial cells under hypoxic conditions, and to further analyze the effect of Dickkopf-1(DKK-1)expression on EMT of lens epithelial cells.METHODS: Human lens epithelial cells(HLEB3 cells)were propagated in vitro and then separated into two groups: one exposed to standard oxygen levels, added DMEM culture solution containing 10% FBS(normoxic group)and another subjected to low oxygen levels(hypoxic group). The hypoxic condition was emulated by applying a concentration of 100 μmol/L cobalt chloride(CoCl2)for 6, 12, 24, and 48h. The utilization of immunofluorescence staining enabled the detection of Wnt3a and DKK-1 expressions, along with the expression and localization of β-catenin protein in these groups. The expression of DKK-1 mRNA was discerned by quantitative real-time polymerase chain reaction(qRT-PCR).RESULTS: Immunofluorescence assays indicated an escalating trend in the Wnt3a and DKK-1 protein expression, which corresponded with the increasing duration of hypoxia. Likewise, an intensified nuclear accumulation of β-catenin protein was observed to be directly proportional to the length of hypoxia treatment. The qRT-PCR demonstrated that the difference in DKK-1 mRNA expression between the normoxic group and the group exposed to hypoxia for 6h was not statistically significant(P>0.05), whereas the DKK-1 mRNA expression of the 12, 24, and 48h hypoxia groups were significantly increased(P<0.001).CONCLUSION: Hypoxia can activate Wnt/β-catenin pathway in lens epithelial cells and induce the expression of DKK-1, thus regulating the Wnt/β-catenin pathway and affecting the EMT process.
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AIM: To investigate the changes of protein expressions in human lens epithelial cells(SRA01/04)undergoing oxidative damage, hoping to provide new protein target for the pathogenesis of age-related cataract(ARC).METHODS: SRA01/04 cells were divided into experimental group and control group. In the experimental group, cells were irradiated with ultraviolet-B(UVB)for 10min to establish the model of oxidative damage, whereas cells in the control group were untreated. Protein expression profile from the two groups was sequenced by isobaric tags for relative and absolute quantitation(iTRAQ). The filtering criteria that fold change &#x003E;1.2 and p&#x003C;0.05 was used to determine the differentially expressed proteins(DEPs). Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)database were utilized for functional enrichment analysis of the top 50 DEPs with either up-regulated or down-regulated significance. Furthermore, Pathway commons software was used to establish the protein-protein interaction(PPI)network.RESULTS: Overall, 552 DEPs were screened out. A total of 176 DEPs were up-regulated in the experimental group compared with the control group, including HMGB1 and USP1, while 376 DEPs were down-regulated, including POLR2A and POLR2B. GO and KEGG enrichment analysis indicated that the top 50 DEPs with up-regulated or down-regulated significance were involved in various crucial biological processes and signaling pathways. PPI network revealed that oxidative damage repair(ODR)-related proteins might play a key role in UVB-induced oxidative damage.CONCLUSIONS: The expressions of multiple proteins, especially ODR-related proteins, can be altered in SRA01/04 cells via UVB irradiation. These findings may provide cellular-related insights into the pathogenesis of ARC and into proteins or pathways associated with therapeutic targets.
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Gigantol is a phenolic component of precious Chinese medicine Dendrobii Caulis, which has many pharmacological activities such as prevent tumor and diabetic cataract. This paper aimed to investigate the molecular mechanism of gigantol in transmembrane transport in human lens epithelial cells(HLECs). Immortalized HLECs were cultured in vitro and inoculated in the laser scanning confocal microscopy(LSCM) medium at 5 000 cells/mL. The fluorescence distribution and intensity of gigantol marked by fluorescence in HLECs were observed by LSCM, and the absorption and distribution of gigantol were expressed as fluorescence intensity. The transmembrane transport process of gigantol in HLECs were monitored. The effects of time, temperature, concentration, transport inhibitors, and different cell lines on the transmembrane absorption and transport of gigantol were compared. HLECs were inoculated on climbing plates of 6-well culture plates, and the ultrastructure of HLECs was detected by atomic force microscopy(AFM) during the transmembrane absorption of non-fluorescent labeled gigantol. The results showed that the transmembrane absorption of gigantol was in time and concentration-dependent manners, which was also able to specifically target HLECs. Energy and carrier transport inhibitors reduced gigantol absorption by HLECs. During transmembrane process of gigantol, the membrane surface of HLECs became rougher and presented different degrees of pits, indicating that the transmembrane transport of gigantol was achieved by active absorption of energy and carrier-mediated endocytosis.
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Humans , Lens, Crystalline/pathology , Cataract/prevention & control , Bibenzyls/pharmacology , Epithelial Cells , Cells, Cultured , ApoptosisABSTRACT
Autophagic flux refers to a series of dynamic process of autophagic bilayer membrane formation, autophagosome formation, autophagolysosomes formation and degradation. The etiology of cataract is complex, including congenital abnormalities in lens development due to genetic mutations, oxidative damage due to aging, abnormalities in glucose metabolism due to diabetes, and proliferation of lens epithelial cells(LECs)stimulated by postoperative inflammatory factor, all of which are associated with the development of cataracts. A growing number of research in recent years have discovered that altering the status of LECs can contribute to the pathophysiological process of cataract by regulating autophagic flux. This review summarized the impacts of autophagic flux regulation on cataract.
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Objective:To explore the inhibitory effect of long non-coding RNA (lncRNA) KCNQ1 overlapping transcript 1 (KCNQ1OT1) by targeting microRNA-199a-5p (miR-199a-5p) on the apoptosis of human lens epithelial cells (LECs).Methods:The anterior lens capsule tissue of 23 age-related cataract patients who underwent cataract surgery in Xinxiang First People's Hospital from December 2018 to August 2019 was collected.At the same time, anterior lens capsules from 20 healthy donor were collected.The expressions of KCNQ1OT1 and miR-199a-5p in the tissues were detected by real-time fluorescence PCR.Human LECs SRA01/04 cultured in vitro were divided into blank control group, model control group, small interfering RNA-negative control (siR-NC) group, siR-KCNQ1OT1 group, miR-NC group, miR-199a-5p group, siR-KCNQ1OT1+ anti-miR-NC group and siR-KCNQ1OT1+ anti-miR-199a-5p group.No intervention was administered to blank control group.Cells in model control group were cultured with 100 μmol/L H 2O 2 for 24 hours to establish oxidative stress injured model, and cells in the other six groups were transfected with corresponding transfection reagents for 6 hours by liposome method according to grouping, and then treated with 100 μmol/L H 2O 2 for 24 hours.The expressions of KCNQ1OT1 and miR-199a-5p in lens anterior capsule tissue and LECs cells were determined by real-time fluorescent quantitative PCR.Cell viability was detected with thiazolyl blue (MTT). Cell apoptosis was analyzed by flow cytometry.The expressions of B-cell lymphoma/leukemia-2 (bcl-2) and bcl-2 related X protein (Bax) proteins were assayed by Western blot.The superoxide dismutase (SOD) activity and malondialdehyde (MDA) content were measured by enzyme-linked immunosorbent assay (ELISA). The targeting relationship between KCNQ1OT1 and miR-199a-5p was verified by dual luciferase reporter experiment.The study protocol was approved by an Ethics Committee of Xinxiang First People's Hospital (No.2019-001). Written informed consent was obtained from relatives of patient. Results:The relative expression of KCNQ1OT1 in the anterior capsule of patients with age-related cataract was 2.41±0.42, which was significantly higher than 0.97±0.19 of normal people, and the relative expression of miR-199a-5p in the capsule of patients with age-related cataract was 0.36±0.12, which was lower than 1.04±0.15 of normal people, and the differences were statistically significant ( t=14.112, 16.507; both at P<0.001). Compared with blank control group, the relative expressions of KCNQ1OT1 and bax protein, cell apoptosis rate and MDA content were significantly increased, and the relative expressions of miR-199a-5p and bcl-2 protein, cell viability and SOD activity were significantly reduced in model control group, showing statistically significant differences (all at P<0.001). Compared with siR-NC group, the relative expressions of KCNQ1OT1 and bax protein, cell apoptosis rate and MDA content in cells of siR-KCNQ1OT1 group were decreased, while the relative expression of bcl-2 protein, cell survival rate and SOD activity were increased, and the differences were statistically significant (all at P<0.05). Compared with miR-NC group, the KCNQ1OT1-wild type (WT) luciferase activity in miR-199a-5p group was significantly decreased, with a statistically significant difference ( t=21.131, P<0.001). The relative expression levels of miR-199a-5p and bcl-2 proteins, cell survival rate and SOD activity were significantly increased, and the relative expression of bax protein, cell apoptosis rate and MDA content were significantly decreased in miR-199a-5p group than those in miR-NC group, and the differences were statistically significant (all at P<0.05). The relative expression levels of miR-199a-5p and bcl-2 proteins, cell survival rate and SOD activity were significantly lower, and the cell apoptosis rate, relative expression of bax protein and MDA content were significantly higher in siR-KCNQ1OT1+ anti-miR-199a-5p group than those in siR-KCNQ1OT1+ anti-miR-NC group, and the differences were statistically significant (all at P<0.05). Conclusions:The inhibition of KCNQ1OT1 can promote the cell viability of human LECs, inhibit H 2O 2-induced cell apoptosis and oxidative stress, and the mechanism may be related to the up-regulation of miR-199a-5p.
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Objective:To explore the effect of knockdown of the homeobox gene paired-box 6 ( Pax6) on the biological behavior and epithelial-mesenchymal transition (EMT) of human lens epithelial cells (LECs). Methods:The SRA01/04 human LECs were divided into small interfering RNA-Pax6 (siRNA-Pax6) group transfected with siRNA-Pax6 and siRNA negative control (siRNA-NC) group transfected with disordered siRNA.Cell survival rate was detected by cell counting kit-8 method at 24, 48 and 72 hours after transfection.Cell cycle distribution and apoptosis were analyzed by flow cytometry at 48 hours after transfection.Migratory capability of cells was examined by cell scratch test at 24 hours after transfection.The mRNA relative expression levels of Pax6, α-crystallin A (CRYAA), α-crystallin B (CRYAB), Sox2, α-smooth muscle actin (α-SMA) and E-cadherin were detected by quantitative real-time PCR at 48 hours after transfection.The relative expression of Pax6 protein was detected by Western blot at 48 hours after transfection.Results:There was a significant difference in cell survival rates at different time points between the two groups ( Fgroup=4.776, P<0.05; Ftime=13.535, P<0.05). The cell survival rate of siRNA-Pax6 group was obviously lower than that of siRNA-NC group at 48 and 72 hours after transfection, and the differences were statistically significant (both at P<0.05). Compared with siRNA-NC group, the proportion of cells in G 0/G 1 phase was significantly increased and the proportion of cells in S phase was significantly reduced in siRNA-Pax6 group ( t=9.971, -5.063; both at P<0.05). The cell migration rate of siRNA-Pax6 group was (19.73±6.07)%, which was lower than (70.56±2.97)% of siRNA-NC group, showing a statistically significant difference ( t=-7.245, P<0.05). The relative expressions of Sox2 mRNA and α-SMA mRNA were lower, and the relative expression of E-cadherin mRNA was higher in siRNA-Pax6 group than siRNA-NC group, with statistically significant differences between them ( t=-23.254, -5.294, 6.062; all at P<0.01). The relative expression of CRYAA mRNA and CRYAB mRNA was significantly higher in siRNA-Pax6 group than siRNA-NC group, and the differences were statistically significant ( t=5.521, 8.270; both at P<0.01). The relative expressions of Pax6 mRNA and protein in siRNA-Pax6 group were 0.27±0.01 and 0.24±0.05, respectively, which were both lower than 1.00±0.05 and 1.14±0.10 in siRNA-NC group, showing statistically significant differences ( t=-14.456, -4.458; both at P<0.001). Conclusions:Silence of Pax6 can suppress the proliferation and EMT of human LECs and enhance the expression of crystallin.
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Objective:To establish an in vitro capsular bag model and compare the inhibitory effects of different 360° square-edge intraocular lens (IOL) on lens epithelial cells (LECs) migration. Methods:In vitro capsular bag model with posterior capsule opacification (PCO) was established using Transwell compartment, cell climbing slices, human collagen type Ⅳ, and IOL.The models were divided into Plate-loop HydroSmart group, C-loop HydroSmart group, and C-compensation-loop Hydrophobic group according to the different square-edge IOL implanted.A blank control group was set using the Transwell compartment without IOL.The early PCO pathological manifestations in lens epithelial cell line SRA01/04 cultured in the Transwell compartment were observed with an inverted microscope.The cell morphology in different groups was observed by hematoxylin and eosin staining.The cell counting and cell migration inhibition rate of anterior capsule and posterior capsule were calculated by Transwell assay and cell-exclusion zone assay, respectively. Results:The early pathological characteristics of PCO, such as early Soemmering ring and small Elschnig pearl, could be found in cells in the in vitro capsular bag model after 48-hour culture.The migrating cells in model groups were fibrous.No changes mentioned above were found in blank control group.The number of migrating cells in the anterior capsule of Plate-loop HydroSmart group, C-loop HydroSmart group, C-compensation-loop Hydrophobic group was 18.80±5.53, 24.67±9.80, and 34.47±10.80, respectively, and the number of migrating cells in the optical area of the posterior capsule of the three groups was 56.43±9.00, 162.20±16.38, and 121.30±12.01, respectively.The cell migration inhibition rate in the anterior capsule of Plate-loop HydroSmart group, C-loop HydroSmart group, C-compensation-loop Hydrophobic group was (92.02±1.94)%, (89.76±3.10)%, (86.27±4.54)%, respectively, and the cell migration inhibition rate in optical area of the posterior capsule of the three groups was (91.60±3.65)%, (70.14±5.35)%, (78.43±3.48)%, respectively.The number of migrating cells in the anterior capsule was lower and the cell migration rate inhibition was higher in Plate-loop HydroSmart group than C-compensation-loop Hydrophobic group, with significant differences (both at P<0.05). The number of migrating cells in the optical area of the posterior capsule and the cell migration inhibition rate was greater than those of C-loop HydroSmart group and C-compensation-loop Hydrophobic group, showing statistically significant differences (all at P<0.001). Conclusions:The in vitro capsular bag model can be used in PCO research.Compared with C-loop HydroSmart IOL and C-compensation-loop Hydrophobic IOL, Plate-loop HydroSmart IOL can more effectively inhibit the migration of LECs to the optical area of the posterior capsule.
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Objective:To explore the role of Grx2 in the pathogenesis of cataract by establishing Grx2 knockout (KO) and knockin (KI) mouse models. Methods:Ten black C57BL/6J mice were selected to make Grx2 KO model ( n=5) and Grx2 KI model ( n=5) using CRISPR/Cas9 system.The offspring mice were sequenced by tail clipping and included in the corresponding experimental group according to the genotype.The general condition and lens opacity was recorded.After the mice were sacrificed, the pathological changes of lens were observed by hematoxylin-eosin staining.The contents of reactive oxygen species (ROS) and 8-hydroxy-desoxyguanosine (8-OHdG) were analyzed by enzyme-linked immunosorbent assay (ELISA).The relative expression levels of Grx2, glutathione (GSH), B-cell lymphoma-2 (Bcl-2) , glutathione disulfide (GSSG) and Bcl-2-associated X protein (Bax) in mice lens were assayed.The use and feeding of experimental animals were in accordance with the Regulations on the Management of Experimental Animals issued by the State Science and Technology Commission.The study protocol was approved by the Ethics Committee of the Second Affiliated Hospital of Chongqing Medical University (No.2020-125). Results:The offspring of Grx2 KO and Grx2 KI homozygous and heterozygous mice were confirmed by tail cutting nested PCR and gene sequencing.Compared with the wild type (WT) mice of same age, the lens opacity of Grx2 KO heterozygous mice occurred earlier, while the lens of Grx2 KI homozygous mice remained transparent all the time.A large number of gaps and vacuoles were found in the lens fibers of 5-month-old Grx2 KO mice.The 8-OHdG content and ROS fluorescence intensity in the lens of 5-month-old Grx2 KO mice were (3.886±0.326)ng/ml and 1 594±132, which were significantly higher than (3.531±0.250)ng/ml and 1 157±123 in WT mice ( t=2.711, P=0.033; t=3.384, P=0.028).The relative expression levels of Grx2, GSH and Bcl-2 in the lens of 5-month-old Grx2 KO mice were 0.23±0.01, 0.70±0.06 and 0.32±0.03, which were significantly lower than 0.52±0.02, 1.04±0.08 and 0.49±0.04 of WT mice ( t=2.815, P=0.020; t=2.457, P=0.033; t=2.279, P=0.041). Conclusions:Grx2 KO and Grx2 KI mouse models are successfully established in this study.The occurrence and development of age-related cataract are accelerated in Grx2 KO mice.
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Objective:To investigate the regulatory effects of microRNA-23b-3p (miR-23b-3p) on the autophagy and apoptosis of human lens epithelial cells induced by high glucose.Methods:Thirty diabetic cataract (DC) patients as DC group and 30 patients with simple cataract as simple cataract group were enrolled in The First Affiliated Hospital of Xi'an Medical University from September 2019 to October 2020.Conventional phacoemulsification and intraocular lens transplantation were performed in both groups.The anterior capsular tissue was collected during the operation.The expression of miR-23b-3p in the anterior lens capsule was detected by real-time fluorescence quantitative PCR (RT-qPCR). Human lens epithelial cell line HLEB3 cells were cultured in vitro and divided into normal control group and high-glucose group, which were cultured in normal and high-glucose medium, respectively.The targeting relationship between proto-cadherin 17 (PCDH17) and miR-23b-3p was predicted according to the bioinformatics database, and was verified by the dual-luciferase reporter gene experiment.High glucose-cultured HLEB3 cells were divided into miR-23b-3p mimics group, negative control (NC) mimics group, NC-siRNA group, PCDH17-siRNA group, miR-23b-3p mimics+ Vector group, miR-23b-3p mimics+ pcDNA-PCDH17 group, and were transfected with corresponding reagents according to grouping.The expression of miR-23b-3p and PCDH17 mRNA was detected by RT-qPCR.The expressions of a mammalian homolog of yeast Atg6/Vps30 (Beclin-1), microtubule-associated protein 1 light chain 3 (LC3B), c-Jun N-terminal kinases (JNK), phosphorylated (p-) JNK, c-Jun, p-c-Jun, B-cell lymphoma-2 (Bcl-2) and Bcl-2 associated X protein (Bax) proteins were assayed by Western blot.The apoptosis rate was detected by flow cytometry.The study protocol was approved by the Ethics Committee of The First Affiliated Hospital of Xi'an Medical College (No.LSL2019037). Written informed consent was obtained from each patient. Results:The relative expression of miR-23b-3p in the anterior lens capsule of DC group was 0.35±0.15, which was significantly lower than 1.00±0.09 of simple cataract group ( t=44.627, P<0.01). There were significant differences in the relative expression levels of miR-23b-3p, LC3B Ⅱ/Ⅰ, Beclin-1, Bcl-2 and Bax proteins among normal control group, high glucose group, high glucose+ NC mimics group and high glucose+ miR-23b-3p mimics group ( F=21.325, 28.318, 17.634, 15.482, 22.325, 26.537; all at P<0.01). Compared with normal control group, the apoptosis rate, LC3B Ⅱ/Ⅰ, Beclin-1 and Bax protein expressions in high glucose group were significantly increased, and the Bcl-2 protein expression was significantly decreased (all at P<0.05). Compared with NC mimics group, the apoptosis rate, LC3B Ⅱ/Ⅰ, Beclin-1, and Bax protein expressions were significantly decreased and the Bcl-2 protein expression was significantly increased in miR-23b-3p mimics group (all at P<0.05). The results of bioinformatics and dual-luciferase reporter gene experiments showed that PCDH17 was a target gene of miR-23b-3p, and the relative expression of PCDH17 mRNA in miR-23b-3p mimics group was significantly lower than that in NC mimics group ( P<0.05). Compared with NC-siRNA group, the apoptosis rate, LC3B Ⅱ/Ⅰ, Beclin-1 and Bax protein expressions in PCDH17-siRNA group were significantly decreased, and the Bcl-2 protein expression was significantly increased ( t=9.116, 12.413, 5.349, 3.273, 8.419; all at P<0.01). There were significant differences in the relative expression levels of p-JNK/JNK, p-c-Jun/c-Jun, LC3B Ⅱ/Ⅰ, Beclin-1, Bcl-2 and Bax proteins in NC mimics group, miR-23b-3p mimics group, miR-23b-3p mimics+ Vector group and miR-23b-3p mimics+ pcDNA-PCDH17 group ( F=24.724, 19.319, 23.418, 17.562, 20.263, 15.249; all at P<0.05). Compared with the miR-23b-3p mimics+ Vector group, the expressions of p-JNK/JNK, p-c-Jun/c-Jun, LC3B Ⅱ/Ⅰ, Beclin-1 and Bax were significantly increased, and the expression of Bcl-2 protein was decreased in miR-23b-3p mimics+ pcDNA-PCDH17 group (all at P<0.05). Conclusions:MiR-23b-3p have a protective effect on HLEB3 cells in a high-glucose environment, mainly by targeting PCDH17 to regulate the JNK signaling pathway to inhibit high glucose-induced autophagy and apoptosis.
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Posterior cataract opacification(PCO)is the epithelial-mesenchymal transformation(EMT)of residual lens epithelial cells(LECs)after cataract surgery, resulting in opaque scar which is one of the main complications of cataract surgery. A large amount of fibronectin(FN)produced by LECs after cataract surgery binds to a variety of cell surface receptors, matrix components and growth factors to regulate cell behavior. The purpose of this article is to review the literatures on the treatment of PCO targeting fibronectin and provide references for clinical treatment of PCO. In this paper, the research status of fibronectin in PCO in recent years is reviewed.
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@#Posterior capsular opacification is the most common complication after cataract extraction, which seriously influences the quality of life of patients. At present, there is no effective measure to prevent posterior capsular opacification. Surgery or Nd:YAG laser is often used in clinical, and a new treatment is urgently needed. Hippo signaling pathway is involved in the steady-state regulation of many mammalian cells and organs. Recent studies have shown that Hippo signaling pathway can regulate the proliferation, apoptosis, differentiation and other behaviors of lens epithelial cells. Hippo signaling pathway may provide a new target in the treatment of posterior capsular opacification. This article reviews the composition, regulatory mechanism of Hippo signaling pathway and its application in posterior capsular opacification. In order to provide a broader idea for the prevention and treatment of posterior capsular opacification.
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@#AIM: To explore the relationship between the protective effect of 17β-estradiol(E<sub>2</sub>)on human lens epithelial cells and pyroptosis. <p>METHODS: Human lens epithelial cells were cultured <i>in vitro</i> and divided into blank control group, H<sub>2</sub>O<sub>2</sub> treatment group, and 17β-estradiol+H<sub>2</sub>O<sub>2</sub> treatment group. Scanning electron microscope to observe the cytological morphology; immunofluorescence technique to detect Gasdermin D(GSDMD)distribution and fluorescence intensity; CCK-8 to detect cell viability; TUNEL to detect cell pyroptosis; Western-blot to detect Cysteinylaspartate specific proteinase-1(Caspase-1), GSDMD, NOD-like receptor protein 3(NLRP3)protein expression level; ELISA to detect interleukin-1β(IL-1β)expression. <p>RESULTS: Compared with the control group, the cell viability of the H<sub>2</sub>O<sub>2</sub> treatment group was significantly decreased, the expression of Caspase-1, GSDMD, and NLRP3 protein were significantly up-regulated, and the secretion of IL-1β was significantly increased. Compared with the H<sub>2</sub>O<sub>2</sub> treatment group, the expression of Caspase-1, GSDMD, and NLRP3 protein in the 17β-estradiol+H<sub>2</sub>O<sub>2</sub> treatment group were down-regulated, and the secretion of IL-1β decreased, and it showed a decreasing trend with the increase of estrogen concentration. <p>CONCLUSION: 17β-estradiol has a protective effect on human lens epithelial cells, and its protective mechanism is related to the inhibition of the pyroptosis process of human lens epithelial cells, and the classical pyroptosis pathway is involved.
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Objective@#To investigate the role of methyl-CpG-binding protein 2 (MeCP2) in the regulation and epithelial-mesenchymal transition (EMT) of human lens epithelial cells (LECs) and its possible mechanism.@*Methods@#Human LEC lines (SRA01/04) were divided into MeCP2-mimic group, MeCP2-NC group and small interferening RNA-MeCP2 (si-MeCP2) group, and MeCP2 analog plasmid, blank plasmid and MeCP2 si-RNA plasmid was used respectively to transfect the cells.The expression of MeCP2 mRNA in the cells was detected by using real-time PCR 24 hours after transfection.At 48 hours after transfection, the migration rate of the cells was evaluated by scratching test, and the expression of Wnt3a protein in the cells was detected by immunofluorescence stainning.The relative expressions of β-catenin, E-cadherin, Vimentin, matrix metallo proteinase (MMP)-9, MMP-7 and secreted frizzled-related protein 5 (SFRP5) proteins in the cells were detected by Western blot.@*Results@#After 24 hours of transfection, the relative expression of MeCP2 mRNA in the cells was significantly different among the MeCP2-mimic group, MeCP2-NC group and si-MeCP2 group (F=4 773.00, P<0.00 1). The migrating rate of the cells in the MeCP2-mimic group, MeCP2-NC group and si-MeCP2 group was (57.45±5.20)%, (32.71±10.02)% and (17.77±9.22)%, respectively, showing a significant difference among the three groups (F=124.00, P<0.001), and the migrating rate of the cells in the si-MeCP2 group was significantly lower than that of the MeCP2-mimic group or MeCP2-NC group (both at P<0.001). The relative expressing intensity (absorbance) of Wnt3a in the cells of the MeCP2-mimic group, MeCP2-NC group and si-MeCP2 group was 75.92±6.10, 52.03±5.22 and 28.75±3.39, respectively, with a significant difference among three the groups (F=221.30, P<0.001), and the relative expressing intensity (absorbance) of Wnt3a in the cells was significantly lower in the si-MeCP2-mimic group than that of the MeCP2-NC group and MeCP2-mimic group (both at P<0.001). The relative expressing level of E-cadherin protein was significantly elevated and the expressions of β-catenin, Vimentin, MMP-9 and MMP-7 were significantly reduced in the si-MeCP2 group compared with the MeCP2-mimnic group and MeCP2-NC group (all at P<0.01). The relative expressing level of SFRP5 protein in the MeCP2-mimic group, MeCP2-NC group and si-MeCP2 group was 27.19±0.03, 47.54±0.05 and 74.93±0.05, respectively, showing a statistical difference among the three groups (F=183.49, P<0.001), and the relative expressing level of SFRP5 in the si-MeCP2 group was significantly higher than that in the MeCP2-mimic group and MeCP2-NC group (both at P<0.001).@*Conclusions@#MeCP2C can promote EMT of human LECs by down-regulating the expression of SFRP5 and therefore activating the Wnt3a/β-catenin signal pathway.
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@#AIM:To observe the expression pattern of Cyclin D1 in human lens epithelial cells(HLECs)after traumatic stimulation in high-glucose culture<p>METHODS: The activity of HLECs was detected by MTT method after incubate with differernt concentration glucose for 24h <i>in vitro </i>to determine the optimal glucose concentration. qRT-PCR and Western blot were used to detect the high glucose pretreatment group and the non-high glucose pretreatment group. The expression of Cyclin D1 in HLECs at different time points after traumatic stimulation was detected.<p>RESULTS: The viability of HLECs were increased when treatment with low concentration glucose, but the concentration should not exceed 25.5mmol/L, or it will inhibit the activity of HLECs; The reasult of high glucose pretreatment group reveal that the expression of Cyclin D1 is down-regulated in a time-dependent manner within a certain time range. While the expression of Cyclin D1 was irregular in the non-pretreatment group, it was increased at the time point of 12h and 48h. The score treatment can up-regulate the expression of Cyclin D1 in HLECs in a certain degreen.<p>CONCLUSION: The effects of glucose on HLECs activity and Cyclin D1 experssion are irrugular. Trauma treatment can stimulate the expression of Cyclin D1 in HLECs to some extent.
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Objective To investigate the role of methyl-CpG-binding protein 2 (MeCP2) in the regulation and epithelial-mesenchymal transition (EMT) of human lens epithelial cells (LECs) and its possible mechanism.Methods Human LEC lines (SRA01/04) were divided into MeCP2-mimic group,MeCP2-NC group and small interferening RNA-MeCP2 (si-MeCP2) group,and MeCP2 analog plasmid,blank plasmid and MeCP2 si-RNA plasmid was used respectively to transfect the cells.The expression of MeCP2 mRNA in the cells was detected by using real-time PCR 24 hours after transfection.At 48 hours after transfection,the migration rate of the cells was evaluated by scratching test,and the expression of Wnt3a protein in the cells was detected by immunofluorescence stainning.The relative expressions of β-catenin,E-cadherin,Vimentin,matrix metallo proteinase (MMP)-9,MMP-7 and secreted frizzled-related protein 5 (SFRP5) proteins in the cells were detected by Western blot.Results After 24 hours of transfection,the relative expression of MeCP2 mRNA in the cells was significantly different among the MeCP2-mimic group,MeCP2-NC group and si-MeCP2 group (F =4 773.00,P＜0.00 1).The migrating rate of the cells in the MeCP2-mimic group,MeCP2-NC group and si-MeCP2 group was (57.45±5.20)％,(32.71± 10.02)％ and (17.77±9.22)％,respectively,showing a significant difference among the three groups (F=124.00,P＜0.001),and the migrating rate of the cells in the si-MeCP2 group was significantly lower than that of the MeCP2-mimic group or MeCP2-NC group (both at P＜0.001).The relative expressing intensity (absorbance) of Wnt3a in the cells of the MeCP2-mimic group,MeCP2-NC group and si-MeCP2 group was 75.92 ± 6.10,52.03 ± 5.22 and 28.75 ± 3.39,respectively,with a significant difference among three the groups (F=221.30,P＜0.001),and the relative expressing intensity (absorbance) of Wnt3a in the cells was significantly lower in the si-MeCP2-mimic group than that of the MeCP2-NC group and MeCP2-mimic group (both at P＜0.001).The relative expressing level of E-cadherin protein was significantly elevated and the expressions of β-catenin,Vimentin,MMP-9 and MMP-7 were significantly reduced in the si-MeCP2 group compared with the MeCP2-mimnic group and MeCP2-NC group (all at P＜O.01).The relative expressing level of SFRP5 protein in the MeCP2-mimic group,MeCP2-NC group and si-MeCP2 group was 27.19± 0.03,47.54±0.05 and 74.93±0.05,respectively,showing a statistical difference among the three groups (F =183.49,P＜0.001),and the relative expressing level of SFRP5 in the si-MeCP2 group was significantly higher than that in the MeCP2-mimic group and MeCP2-NC group (both at P＜0.001).Conclusions MeCP2C can promote EMT of human LECs by down-regulating the expression of SFRP5 and therefore activating the Wnt3a/β-catenin signal pathway.
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A contributory role of oxidative stress and protection by antioxidant nutrients have been suspected in cataract formation. Ganoderic acid A (GAA), an effective lanostane triterpene, is widely reported as an antioxidant. The aim of this study is to investigate the potential effects of GAA on cataract formation. After lens epithelial cells (LECs) were exposed to UVB radiation for different periods, cell viability, apoptosis-related protein levels, malondialdehyde (MDA) and superoxide dismutase (SOD) activities were monitored. We found that cell viability, the Bcl-2/Bax ratio and SOD activity were increased, while Cleaved caspase-3 levels and MDA activity were decreased compared with those in UVB-impaired LECs after GAA treated. Furthermore, GAA activated PI3K/AKT in UVB-impaired LECs and effectively delayed the occurrence of lens opacity in vitro. In conclusion, these findings demonstrated that GAA exhibited protective functions in SRA01/04 cells and rat lenses against UVB-evoked impairment through elevating cell viability and antioxidant activity, inhibiting cell apoptosis, activating the PI3K/AKT pathway and delaying lens opacity.
Subject(s)
Animals , Humans , Rats , Apoptosis , Cataract/prevention & control , Cell Line , Cell Survival , Epithelial Cells/radiation effects , Heptanoic Acids/pharmacology , Lanosterol/pharmacology , Lens, Crystalline/radiation effects , Malondialdehyde/metabolism , Superoxide Dismutase/metabolism , Ultraviolet Rays/adverse effectsABSTRACT
@#AIM: To observe the effect and mechanism of MicroRNA-34a on senescence and apoptosis of human lens epithelial cell line SRA01/04.<p>METHODS: MicroRNA-34a expression levels in ARC lens and transparent lens epithelial cells were detected by qRT-PCR. MicroRNA-34a mimics, MicroRNA-34a inhibitors and empty liposome(control group)were transfected into SRA01/04 cells by liposome transfection kit. Annexin V-FITC/PI double staining was used to detect the effect of MicroRNA-34a on the apoptosis of human lens cell line SRA01/04. The expression of Cdc42 and Rac1 protein was detected by western blot. <p>RESULTS: The expression level of MicroRNA-34a in anterior capsular tissue of transparent lens was significantly lower than that in ARC anterior capsular tissue(<i>P</i><0.05). The positive rates of SA-β-gal in the MicroRNA-34a mimics group, the control group and the MicroRNA-34a inhibitors group were(87.56±2.34)%,(12.22±2.74)% and(3.45±0.45)%, respectively. The positive rates of SA-β-gal in the MicroRNA-34a mimics group was significantly higher than the control group, while the SA-β-gal positive rate in the MicroRNA-34a inhibitors group was significantly lower than that in the control group(<i>P</i><0.05). The apoptosis rate of the MicroRNA-34a inhibitors group, control group and MicroRNA-34a mimics group were(5.87±1.22)%,(12.26±2.14)% and(29.45±3.12)%, respectively. The apoptosis rate of the MicroRNA-34a mimics group was significantly higher than that of the control group, while that of the MicroRNA-34a inhibitors group was significantly lower than that of the control group(<i>P</i><0.05). The expressions of Cdc42 and Rac1 in the MicroRNA-34a mimics group were significantly higher than those in the control group(<i>P</i><0.05), while the expressions of Cdc42 and Rac1 in the MicroRNA-34a inhibitors group were significantly lower than those in the control group(<i>P</i><0.05).<p>CONCLUSION: MicroRNA-34a may promote the senescence and apoptosis of human lens epithelial cells by up-regulating Cdc42 and Rac1.
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@#AIM: To investigate the regulation of autophagy on high glucose-induced epithelial-mesenchymal transition(EMT)in human lens epithelial cells.<p>METHODS: In order to investigate the changes of EMT and autophagy induced by high glucose, HLE-B3 cells were divided into two groups. In NC group, cells were cultured in DMEM with 5.5mmol/L glucose, and in HG group, cells were treated with DMEM in addition with 30mmol/L glucose for 12h, 24h, and 48h. Western blot was used to detect the expression of EMT-marker proteins(E-cadherin and α-SMA)and autophagy-marker proteins(LC3, Beclin 1 and SQSTM1/p62). Wound healing assay was conducted to observe the migration ability. To investigate the regulation of autophagy on EMT, we employed rapamycin, an agonist of autophagy. HLE-B3 cells were divided into 4 groups. Two of them were mentioned as above, and the other two groups were treated with high glucose combined with DMSO(DMSO)and high glucose combined with 200nmol/L rapamycin(RAPA), respectively. Migration ability of cells was evaluated by Transwell assay. Expressions of proteins, such as EMT marker proteins, molecules in TGF-β signaling pathway(TGF-β2, Smad2/3, p-Smad2/3, Snail), and autophagy markers were detected by Western blot. The intracellular co-localization of SQSTM1/p62 and Smad2/3 was observed by immunofluorescence staining, and their interaction was confirmed by co-immunoprecipitation assay. <p>RESULTS: The expression of E-cadherin, LC3 Ⅱ/Ⅰ, and Beclin 1 in HLE-B3 cells of HG group gradually decreased(<i>F</i>=67.52, 163, 206; all <i>P</i><0.0001), the expressions of α-SMA, SQSTM1/p62 increased with time(<i>F</i>=53.37, 302.1; all <i>P</i><0.0001), and cell migration also increased compared with the cells in NC group(all <i>P</i><0.001), indicating that high glucose stimulated EMT and suppressed autophagy. After treatment with rapamycin, the expressions of LC3 Ⅱ/Ⅰ and E-cadherin increased, the expressions of α-SMA, p-Smad2/Smad2, p-Smad3/Smad3 and Snail decreased(all <i>P</i><0.05), and the expressions of TGF-β2 did not change(all <i>P</i>>0.05)in RAPA group compared with HG group and DMSO group, cell migration was also suppressed(all <i>P</i><0.001), indicating that Rapamycin down regulated the expressions of molecules in TGF-βsignaling pathway after activation of autophagy, which resulted in inhibiting EMT. Immunofluorescence staining showed co-localization of SQSTM1/p62 and Smad2/3 in cytoplasm. Co-immunoprecipitation confirmed the combination between SQSTM1/p62 and Smad2/3.<p>CONCLUSION: High glucose stimulates the process of EMT and suppresses the autophagy in HLE-B3 cells. Autophagy regulates EMT by interacting with Smad2/3 via SQSTM1/p62, altering the amount of Smad2/3 which works in the TGF-β signaling pathway.