The Detection And Analysis Of LEP503 Gene Expression In LECs In Different Age Of Cataract Patients

Objective: It is known that cataract is the worldwide principal blindness-incurring disease, but the pathogenesis remains unclear because of its complication so far. Studies in recent years by professor Yi Wen showed that the occurrence of cataract had close relationship with disorder of gene expression. The genes specifically expressed in lens epithelial cells may play a key role in the process of growth, differentiation and repair of injuries in lens epithelium. It is not reported that the exclusive gene of lens epithelial cells, LEP503 (lens epithelium gene product 503, LEP503), either is expressed in cataract patients, or has involved in proliferation in patients' lens epithelial cells, while LEP503 is expressed in normal lens epithelium or LECs in culture according to the investigation reports. Aiming at discussion of the mechanism of cataract by investigating the expression of LEP503 gene, which is specifically expressed in lens epithelial cells, in different age of cataract patients and normal persons.Methods: Anterior capsular membranes of lens from different age of cataract patients were divided into two groups, the youth group (under 50years) and the senile group (above 50years), and the anterior capsular membranes of lens of corpse without cataract were collected to be control group. The proportion between male and female in each of groups was 1:1 so as to exclude the effects of gender. The expression of LEP503 gene was detected by RT-PCR, LEP503 protein by Western-Blotting, and electrophoresis strap's density aiming at comparing the difference of LEP503 expression between cataract group and control group by Gel Imaging Assay system. Data was analyzed by T test and linear regression statistically with SPSS12.Results: 1.RT-PCR showed good balance of age in the cataract group and control group, and the parameters are comparable. All the samples expressed LEP503 gene, and the expression level in cataract group was higher than that of control group. There was significant difference between cataract patients and normal persons P<0.01, and between cataract patients in youth group and senile group as well, but not in control group P=0.75. There is a linear relationship between the expressing level of LEP503 and patient's age. 2.Western-Blotting showed the protein expression level of LEP503 was more notable in cataract group than in control group, and the level increasing in cataract group accorded with the rising of patient's age, whereas there is no obvious rules of LEP503 expression among the control group.Conclusion: 1.Cataract patients express LEP503 and the expression level is higher than that of normal persons. 2.There is a linear relationship between the expressing level of LEP503 and cataract patient's age. 3.There is no direct relationship between the expression of LEP503 and the proliferation of lens epithelial cells. 4.LEP503 may play different roles in the pathogenesis of senile and youth cataract.