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<p><b>BACKGROUND</b>Contrast sensitivity (CS) testing can detect differences in functional vision and is highly correlated with visual performance. This study was designed to investigate the association between CS and the grading score using the lens opacities classification system (LOCS) III as well as the association between CS and visual acuity (VA) in nuclear or cortical age-related cataract (ARC) patients.</p><p><b>METHODS</b>A total of 270 eyes with ARC and 30 control eyes were divided into nuclear opacity (NO), nuclear color (NC), cortical cataract (C) based on LOCS III. The CS values measured at all spatial frequencies under photopic and glare conditions that resulted in contrast sensitivity function (CSF) were evaluated, and LogMAR VA was tested with the Early Treatment Diabetic Retinopathy Study (ETDRS) chart. The correlation between CSF and LOCS III grading scores, and between CSF and LogMAR VA were analyzed.</p><p><b>RESULTS</b>Compared to the controls, CSF of the nuclear or cortical ARC significantly declined. There are significant correlation between CSF and LogMAR VA, and between CSF and LOCS III grading scores. Compared to the VA, a stronger correlation existed between CSF and LOCS III grading score than that of LogMAR VA and LOCS III grading score. CS at some spatial frequencies is significantly influenced with LOCS III grading score.</p><p><b>CONCLUSIONS</b>CSF significantly declined with the increasing ARC grading scores. Comparing to VA, CSF reflected the severity of cataract more comprehensively. CS at low spatial frequency is significantly influenced by ARC. Therefore, CS is more precise than VA in assessing the visual function of ARC patients.</p>
Subject(s)
Aged , Female , Humans , Male , Middle Aged , Cataract , Classification , Contrast Sensitivity , Physiology , Visual AcuityABSTRACT
Background Ultraviolet radiation is one of factors of the formation of age-related cataract.Indole-3-carbinol(I3C) is a plant chemical material with inhibitory effect on oxidative-induced cell damage and formation of amyloid fibrils,and the oxidative damage and amyloid fibrils are associated with cataract.However,the relationship between I3C and α-crystallin is in study. Objective This study was to evaluate the effects of ultraviolet-B laser irradiation on the secondary structure of α-crystallin and to explore the protection of I3C to chaperone activity of α-crystallin. Methods The fresh eyeballs were obtained from 1-year-old cattle to prepare the purified lens α-crystallin by gel chromatography.α-Crystallin was isolated from cattle lenses using gel chromatography.The purified α-crystallin was collected using fast protein liquid chromatography ( FPLC ) and exposed to 1:308 nmultraviolet-B at different irradiation intensities ( 23.75,118.75,475.00,1187.50,2375.00,4750.00,11 875.00,23 750.00 mJ/cm2 ) and then to ultraviolet-B 2:308 nm with irradiation intensities of 28 535.00,6730.00,3435.00,1910.00,1040.00 mJ/cm2.Ultraviolet-absorbance spectra,tryptophan fluorescence and N-formylkynurenine (N-FK)fluorescence spectra of both irradiated and non-irradiated α-crystallin were measured.I3C at the concentrations of 50 μmol/L and 100 μmoL/L were added to the α-crystallin solution to perform a catalase (CAT) thermal aggregation to confirm the chaperone activity of the α-crystallin,and the α-crystallin solution without any I3C was used as control.The ratios of A360 between various intervene groups with control group were calculated using spectrophotometry.Results The A280 values of the α-crystallin declined to 10％ at the ultraviolet-B irradiation intensity of 1187.5 mJ/cm2 and that at the intensity of 23.75 J/cm2 lowed to 2％.A negative correlation was seen between the ultraviolet-B irradiation intensity and the A280 value of the α-crystallin (R2=0.925 ) and a positive correlation was found between ultraviolet-B with N-FK ( R2 =0.949 ).Ultraviolet-B irradiation intensity showed a negative correlation with Trp fluorescence intensity (R2 =0.996 ).CAT hot condensed experiment revealed that after addition of different concentrations of indole-3-carbinol,the relative A360 values at various ultraviolet-B irradiation group were significantly higher than those of the control group (P =0.000),and the decreasing degree of chaperone activity of α-crystallin was lower than that of the control group ( P =0.000 ). Conclusions The study suggests that I3C can protect the chaperone activity of α-crystallin from photooxidation,and the ultraviolet-B laser may be a good exposure source compared with ultraviolet lamp.The ultraviolet-B laser irradiation causes the alteration of structure and chaperone activity of α-crystallin.
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Background Oxidative stress-induced apoptosis of human lens epithelial cells (LECs) is associated with c-Jun N terminal kinase (JNK) pathway.Quercetin possesses the antioxidation by inhibiting the JNK pathway.However,whether quercetin can protect LECs from the oxygen-induced damage is still not proved.Objective This study attempted to invatigate the effects and its mechanism of quercetin against hyperbaric oxygeninduced LECs apoptosis. Methods Human LECs line SRA01/04 was cultivated and passaged in MEM medium containing 10％ fetal bovine serum and 0.5％ non-essential amino acids for 2 hours,with or without 20 μmol/LSP600125 or 1 μmol/L quercetin prior to exposure to hyperbaric oxygen.Each exposure session remained 6 hours in 99％ O2 and 1％CO2 with a pressure chamber at 588 kPa.The viability of human LECs was detected by MTT.Cell apoptosis was assessed by flow cytometer using Annexin V-FITC apoptosis detection.The expression of JNK/p-JNK,c-Jun/p-c-Jun,caspase 3 and caspase 9 were detected by Western blot. Results LECs viability (A570 ) was 0.835 ±0.082,0.450±0.083,0.654±0.079,0.649±0.090 respectively in the blank control group,hyperbaric oxygen exposed group,hyperbaric oxygen+SP600125 group and hyperbaric oxygen+quercetin group.The A570 in the hyperbaric oxygen exposed group was significantly lower than the blank control group ( P =0.000),but those in hyperbaric oxygen + SP600125 group and hyperbaric oxygen+quercetin group were significantly higher than the hyperbaric oxygen exposed group ( P =0.003,0.002 ).The numbers of apoptosis cells were 3.17 ±0.74,19.77 ± 1.44,8.45 ±0.93,7.79 ±0.78 respectively in the blank control group,hyperbaric oxygen exposed group,hyperbaric oxygen+SP600125 group and hyperbaric oxygen+quercetin group.Apoptotic LECs were significantly increased in the hyperbaric oxygen exposed group compared with the blank control group ( P=0.000),but those in the hyperbaric oxygen+SP600125 group and hyperbaric oxygen+quercetin group were significantly reduced in comparison with hyperbaric oxygen exposed group (both P=0.000).In additional,expressions of p-JNK,p-c-Jun,caspase 3 and caspase 9 proteins in the cells were elevated in the hyperbaric oxygen exposed group compared with the blank control group (all P =0.000 ),however,those in the hyperbaric oxygen + SP600125 group and hyperbaric oxygen + quercetin group were declined when compared with the hyperbaric oxygen exposed group( all P＜0.05 ). Conclusions JNK pathway is involved in the apoptotic procedure of human LECs induced by oxygen stress.SP600125 and certain concentration of quercetin can interdict the JNK signal pathway and endogenous apoptosis of LECs and further alleviate hyperbaric oxygen-induced damage of LECs.
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Background Epithelial-mesenchymaltransition (EMT)isamajorcontributortothe pathogenesis of posterior capsular opacification(PCO).Kruppel-like factor 6 (KLF6) is a zinc finger protein,which can be stimulated by high glucose in proximal tubule cells and involved in transforming growth factor beta (TGF-β)induced EMT of diabetic nephropathy.ObjectiveThis study was designed to investigate the effect of high glucose on the expression of KLF6 and its target genes( TGFB1,TGFBR1,COLIA1,HSP47) in human lens epithelial cells (LECs).MethodsHuman LECs(SRA01/04) were cultured and exposed to different concentration of glucose.The expressions of KLF6 mRNA and protein were analyzed by real time polymerase chain reaction( real time PCR) and western blot after treatment with high glucose.The expressions of KLF6 target genes were analyzed by real time PCR to evaluate the EMT of SRA01/04 cells.ResultsCompared with the control group(5.5 mmol/L),the relative mRNA levels of t-KLF6 and wt-KLF6 in SRA01/04 treated with high glucose(22.2,44.4,66.6 mmol/L) increased obviously (F =72.53,42.02,P＜0.01 ).Then,the concentration of 22.2 mmol/L was used in the next experiments.The relative mRNA levels of t-KLF6 and wt-KLF6 increased to the peaks after treatment with high glucose for 12 h,and began to decrease after 24 h until lower levels after 48 h ( F =100.12,125.52,P ＜ 0.01 ).Western blot showed that the expression of KLF6 protein was also upregulated by high glucose treatment.With the promotion of the expression of KLF6 gene,the relative mRNA levels of TGFB1,TGFBR1,COLlAl and HSP47 of treated cells also respectively increased after treatment for 12 h,and began to decrease after 24 h until nearly at the levels of the control groups after 48 h( F=6.73,162.35,64.39,12.05,P＜0.05 ).ConclusionsIt was concluded that high glucose induced the expression of KLF6 in human LECs,and KLF6 transiently stimulated the expression of target genes TGFB1,TGFBRl,COLlAl and HSP47 which were mainly involved in the mechanism of EMT.