Expression Of RAGE In The Anterior Capsule Of Diabetic Cataract And Human Lens Epithelial Cells Cultured In Vitro

ObjectiveTo study the expression of the receptor for advanced glycation end products(RAGE)in the anterior capsule of patients with diabetic cataract(DC)and age-related cataract(ARC),in vitro experiments to detect the effects of different concentrations of high glucose on the expression of RAGE and apoptosis of human lens epithelial cells(LECs),providing new ideas for the study of the pathogenesis of DC and prevention methods.Methods(1)Twenty-six patients with DC(30 eyes)and 24 patients with ARC(30 eyes)were selected.The lens anterior capsule was collected.For DC patients,collected the datum including age,duration of diabetes mellitus,and hemoglobin A1c(Hb A1c)level.For ARC patients,record age.Western blot(WB)method was used to detect the expression of RAGE in the anterior capsule.ARC patients were divided according to age: A1 group(50-69 years)and A2 group(70-89 years).DC patients were divided according to age and Hb A1 c level: D1 group(50-69 years old,Hb A1 c 7.0%-12%),D2 group(50-69 years old,Hb A1 c 4.0%-7.0%),D3 group(70-89 Years old,Hb A1 c was 7.0%-12%),group D4(70-89 years old,Hb A1 c was 4.0%-7.0%).The expression of RAGE in DC and ARC anterior capsules was compared and analyzed with their clinical data.(2)Human LECs were cultured in vitro,and grouped into: group A0: DMEM culture medium;group A1: culture medium added with 10mmol/L glucose;group A2: culture medium added with 20mmol/L glucose;group A3: culture medium added with 30mmol/L glucose,group A4: culture medium added with 30mmol/L mannitol.All cells were cultured on a six-well plate with two duplicate wells in each group.After 48 hours of culture,the expression of RAGE was detected by WB method,and the apoptosis rate was detected by flow cytometry.The difference of the gray value of RAGE protein bands and the apoptosis rate of each group of cells cultured in different medium were compared.The correlation between the apoptosis rate and the concentration of glucose added to the culture medium was analyzed.SPSS 24.0 software was used for statistical analysis.First,Kolmogorov-Smirnov was used to test the normality of the data.If the data conforms to the normal distribution,a one-sample t test is used.If it does not,the Wilcoxon test is used.The correlation between apoptosis rate and glucose concentration was analyzed by spearman rank correlation.Results(1)The expression degree of RAGE in patients' anterior capsule was:(1)for ARC patients,the gray value of group A2 was higher than group A1,indicating that the older the ARC patients,the higher the RAGE expression degree of the anterior capsule;for DC patients,the gray value of group D1 was higher than group D2,and the gray value of group D3 was higher than group D4,indicating that the higher the level of Hb A1 c in DC patients,the higher the RAGE expression degree of the anterior capsule;(3)for patients of different age,the gray value of group D1 was higher than group A2 and group D4,indicating that the effect of Hb A1 c level on the degree of RAGE expression is greater than that of age.(2)(1)The expression degree of RAGE in the cells with glucose added to the culture medium was higher than that in the DMEM medium,and the difference was statistically significant(P=0.001).The expression degree of RAGE in the cells with glucose added to the culture medium was higher than that in the culture medium added with mannitol,and the difference was statistically significant(P<0.001).(2)The apoptosis rate of each group with glucose added to the culture medium was higher than that of the DMEM culture medium group,and the difference was statistically significant(P=0.002).The apoptosis rate of each group with glucose added to the culture medium was higher than that of the group with mannitol added to the culture medium,the difference was statistically significant(P=0.002).The apoptosis rate of each group with glucose added to the culture medium was positively correlated with the added glucose concentration(correlation coefficient r=0.892,P <0.001).ConclusionThe expression of RAGE in the anterior capsule of DC patients is higher than that of ARC.At the same age,when the Hb A1 c level is higher,the RAGE expresses higher;when the glucose concentration is added more,the RAGE expression of human LECs and the apoptosis rate of LECs is higher.It is speculated that RAGE may be involved in the formation of cataracts and accelerate the progression of cataracts in patients with diabetes mellitus.