Study On The Apoptosis Of Lens Epithelial Cells And Apoptosis-related Factors In Age-related Cataract

Cataract is the primary disease that results in blindness all over the world, and the half of all blindnesses are caused by it in China.The most primary composing of cataract is the age-related cataract(ARC)in our country.At present,the pathogenesis of the age-related cataract is not very clear.Now,the domestic and foreign researches have proved that the cause of the ARC is very complicated.As far as risk factors be concerned,there are age,sex,smoking, diet,hypertension,diabetes,ultravioled ray radiation,oxidation and so on.In addition,the change of len's environment,some of growth factors and cell factors are also concerned with ARC.Recently,more and more epithelogy data have revealed that gene and heredity factors play an important role in the cause of ARC.At the same time,a large number of experiments have also proved that some of related genes occured special change and the change of related function in the development of ARC.The basis of the pathology and physiology about ARC were mainly showed in two aspect:the apoptosis of lens epithelial cells and the change of crystallins.So,we study apoptosis of lens epithelial ceils and apoptosis- related factors in ARC and try to find the cause of ARC in order to provide a new approach for the prevention and treatment of ARC.METHOD1,Apoptotsis cells of lens epithelia cells from ARC and control groups were detected with TUNEL,and apoptotsis rate of LEC was calculated.2,Protein expressions of bcl-2,p53,c-myc and so on in lens epithelial cells of ARC patients were detected by immunohistochemical technique.3,RT-PCR method was used to study mRNA expression levels of bcl-2, p53,c-myc and so on in lens epithelial cells of ARC.4,Polymerase chain reaction(PCR)method was used to detect the GSTμgene of the ARCand healty controls.RESULT1,Many apoptotic cells were observed in the LEC of age-related cataract patients and the control's lens epithelial cells were normal.The Apoptotic cell rate was 7.1%to 35.6%in ARC,and control was less than 0.05%.There was significant differences between two groups.2,p53,bcl-2,c-myc didn't almost express in normal lens epithelial cells, but can be observed in lens epithelial cells of ARC.The difference between ARC and control was remarkable.The mRNA expression levels of p53,c-myc and so on were higher in ARC than in control.There was no bcl-2 protein expression in the lens epithelial cells of ARC and control.3,TGF-β₂ mRNA's expression level is higher inARC than in control.4,Under normal circumstances,there were lower expression levels of HSP27 and HSP70 in the lens epithelial cells,Their expression levels were higher in ARC than in normal.5,The GSTμgene deletion rate of the age-related cataract patients was above 51.67%and was only 31.67%in control.The difference reached remarkable level.CONCLUSION1,ARC is a kind of multi-cause disease.2,The apoptosis of the lens epithelial cells is pathology basis of ARC. The higher expression of accelerating apoptotic gene and no expression of restraining apoptotic gene could be concerned with the apoptosis of LEC and lead to ARC.3,The stress expression of HSP27 and HSP70 reveal that they participate in protection of anti-stress injury of the lens epithelial cells.4,TGF-β₂ is remarkable higher in ARC than in control group which suggests TGF-β₂ plays an important role in the development of ARC.5,To GSTμgene deletion patients,the onset risk of the cataract is higher than normal crowd.