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Objective To explore the effects of estradiol on the telomerase activity and apoptosis of lens epithelial cells and its mechanisms.Methods Fifty adult female Sprague-Dawley rats were randomly divided into five groups (n =10):ovariectomized group,estradiol group 1,estradiol group 2,estradiol group 3 and sham group.All rats were prepared for ovariectomized models except that of the sham group.After 2 weeks of the operation,rats in the 5 groups were given naphthalene solution through a stomach tube,and meanwhile,estradiol group 1,estradiol group 2,estradiol group 3 received estradiol valerate with the dose of 0.21 mg · kg-1 · d-1,0.42 mg · kg-1 · d-1 and 0.84 mg · kg-1 · d-1,accordingly,while rats in the ovariectomized group and sham group were given 9 g · L-1 Nacl by stomach perfusion with a dose of 0.42 mg · kg-1 ·d-1.Then,the opacity of the lens in each group was examined by a slit lamp microscope every week.After 12 weeks of naphthalene solution administration,all rats were sacririced and the serum estradiol concentration was determined by radioimmunoassay.Next,the lenses were taken out,and TERT mRNA expression of lens epithelial cells (LEC) was measured by RT-qPCR,and finally,the apoptotic rate was detected by TUNEL method.Results The opacity of lens in the ovariectomized group was different from that in the estradiol group 1,estradiol group 2,estradiol group 3 and sham group,with statistical significances (all P ＜ 0.05),and the opacity of lens in the estradiol group 1,2,3 and sham group were mild and occurred later.The serum estradiol concentration in the ovariectomized group (8.19 ± 1.45)ng · L-1 was significantly lower than that of estradiol groupl,2,3 and sham group,and there were significant differences (all P ＜ 0.05).Thc relative expression of TERT mRNA in LEC in the ovariectomized group (0.371 2-±0.056 4) was significantly lower than that in estradiol group 1,2,3,but the apoptotic rate of LEC (0.602 1 ±0.010 8) was obviously higher than that of estradiol group 1,2,3 in a dose-dependent manner,and there were significant differences (all P ＜ 0.05).Pearson correlation analysis showed the relative expression of LEC TERT mRNA in rats was negatively correlated with the apoptosis rate(r =-0.859,P ＜ 0.05).Conclusion Estradiol can up-regulate TERT mRNA expression and enhance telomerase activity of LEC in naphthalene-induced ovariectomized female rats in a dose-dependent manner.Estradiol can inhibit the LEC apoptosis in naphthalene-induced ovariectomized female rats,and the mechanism may be related to the increase of telomerase activity in the LEC.
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Objective To observe the protective mechanisms of zingiber officinalis extract on the lens of diabetic rats induced by streptozotocin (STZ).Methods Totally 60 SD rats were randomly divided into A group (normal control rats),B group (diabetic rats),C1 group (DM +50 mg · kg-1 ginger gavage),C2 group (DM + 100 mg ·kg-1 ginger gavage) and C3 group (DM + 300 mg · kg-1 ginger gavage).Each group had 12 rats.And rats in A group received intraperitoneal injection of the same volume of normal saline,while the other groups were intraperitoneally injected with 65 mg · kg-1streptozotocin (STZ).When the animal model was successfully established,both A group and B group were administered orally with normal saline,and the C1,C2 and C3 groups were administered orally with ginger rhizome extract.The changes in blood glucose and lens were observed every week.The rats were sacrificed in succession at 4 week,8 week,12 week,and the lens was removed immediately.The content of aldose reductase (AR) was detected by ELISA,and the expression of glycosylation end products (AGEs) was detected by Western blot.The superoxide dismutase (SOS) activity and malondialdehyde (MDA) content were also detected.Fluorescent Tunel staining was used to detect the apoptosis of the lens epithelial cells.And finally,scanning electron microscopy was used to observe the ultrastructural changes in the lens.Results The activity of SOD in the lens of diabetic rats showed a decreasing trend with statistical significance (all P ＜ 0.05).Changes in the content of MDA in the lens of rats in B,C1,C2 group were statistically significant in 4,8 and 12 weeks after successful modeling (all P ＜ 0.05),but no significant difference in A group and C3 group (both P ＞ 0.05).The persistent increase of AR in group B (P =0.003).The content of AR of the lens in C1,C2,C3 group showed a decreasing trend,and the differences were statistically significant (all P ＜ 0.05).There were significant differences in the expression of AGEs in C1,C2 and C3 group (all P ＜ 0.05).The degree of cortical fiber destruction in group B was progressively aggravated,but the degree of cortical destruction in C1,C2 and C3 group decreased with the increase of ginger gavage concentration through the scanning electron microscopy.It was observed that there was no significant difference in the apoptotic rate of LECs in A group (P =0.191),but the apoptosis of LECs in the rest group showed a rising trend,and the differences were statistically significant (all P ＜ 0.05).Conclusion The effects of ginger gavage extract can delay the opacification of lens and slow down the diabetic development in rats with a dose-independence manner.Ginger gavage extract may play a protective role on the lens of diabetic rats by inhibiting the activity of AR,oxidative stress and the production of AGEs as well as suppress the apoptosis of lens epithelial cells.
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AlM:To understand the effect on comprehensive ability of“Teaching-learning transaction” professional education of ophthalmic postgraduates which involving the teachers and students to participate in, and to explore new education model for ophthalmic postgraduate.METHODS:We carried out retrospective investigation questionnaire in the 31 ophthalmic postgraduates of Luzhou Medical College 2010 ~ 2014 grade and the 47 medical staffs of Department of Ophthalmology of the Affiliated Hospital of Luzhou Medical College, to clarify the new professional education model whether could improve the comprehensive ability of ophthalmic postgraduates or not. RESULTS: Carrying out the “ Teaching - learning transaction” professional education could improve the comprehensive ability of ophthalmic postgraduates.CONCLUSlON: Putting teaching and learning together can improve and promote each other, and it is helpful to cultivate comprehensive ability of ophthalmic postgraduates.