Objective To observe the inhibition effect of curcumin on the proliferation of rabbit retinal pigment epithelial (RPE) cells and investigate its mechanism. Methods The 4th generation of RPE cells were selected and divided into curcumin group and blank control group. The concentration of curcumin included 10, 15, and 20 mu;g/ml. The MTT assay was used to evaluate the inhibition effect on the proliferation of RPE cells at the 24th, 48th, 72nd and 96th hour after cultured with curcumin (10, 15, and 20 mu;g/ml). The IC50 value of curcumin at different time points were calculated by Linear Regression. Flow cytometry was used to detect the effect on the cell cycle at the 72nd hour after cultured with curcumin (15 mu;g/ml); the expression and apoptosis of proliferating cell nuclear antigen (PCNA) were also determined at the 24th,48th, and 72nd hour after cultured with curcumin (15 mu;g/ml) respectively. The configuration of RPE cells were observed by transmission electron microscope. Results The IC50 value of curcumin at the 24th,48th, 72nd and 96th hour was 29.31, 17.50, 13.24, and 10.99 mu;g/ml respectively. Cell cycel analysis indicated that curcumin blocked cells in G0/G1 phase. At the 24th, 48th, and 72nd hour after cultured with curcumin (15 mu;g/ml), the expression of PCNA of RPE cells were 565.04plusmn;23.60, 473.61plusmn;36.88, and 396.15plusmn;32.45; the apoptosisrate were （12.83plusmn;0.13）%，（32.27plusmn;4.51）%，（56.81plusmn;8.67）%, respectively. The differeces of curcumin groups compared with the control group were significant (P＜0.05). Apoptosis of RPE cells was observed under transmission electron microscope. Conclusions Curcumin can inhibite the proliferation of RPE cells by inhibit the synthesization of PCNA and inducing the apoptosis of RPE cells. Curcumin may become a potential drug to prevent and treat PVR.
Objective To observe the effect of medicineinduced posterior vitreous detachment (PVD) on proliferative vitreoretinopathy (PVR). Methods PVR was induced in the left eyes of 24 pigmented rabbits by intravitreal injection with platelet rich plasma. The rabbits were randomly divided into two experimental groups (group A and B) and one control group with 8 eyes in each group. Three hours later, the eyes in group A and B and the control group underwent intravireal injection with 1 U plasmin 0.05 ml+20 U hyaluronidase 0.05 ml, plasmin 0.1 ml, and balance salt solution 0.1 ml, respectively. The grade of PVR was recorded 1, 7, and 28 days after the intravitreal injection, and the eyes were examined by flash electroretinogram (FERG), B-scan, and retinal histopathological examination. Results The PVR models of rabbit eyes were induced successfully. On the 7th day after injection, complete and partial PVD was found in 5 and 3 eyes respectively in group A; partial PVD in 5 eyes and no complete PVD was observed in group B; there was no PVD in the other 3 eyes in group B and also in the eyes in the control group. On the 28th day after intravitreal injection, PVR grade of group A and B were both obviously lower than that of the control group（D=75.6, 98.9；P=0.003，P=0.011）; On the 7th and 28th day after injection, the b-wave amplitude in group A and B was significantly higher than that in the control group; PVR grade of the PVD eyes was lower than that of nonPVD eyes; PVR grade of the complete PVD eyes was only 0～1. Conclusions Three hours after the PVR models of rabbit eyes were induced, complete PVD induced by intravitreal injection of plasmin combined with hyaluronidase could prevent the development of PVR of rabbit eyes in some degree; partial PVD induced by plasmin alone or combined with hyaluronidase could relieve the development of PVR.
Objective To observe the surgical results of the patients with persistent hyperplastic primary vitreous (PHPV). Methods Clinical data of 16 eyes of 16 patients with PHPV who had undergone retina surgery were retrospectively analyzed. The patient, 7 males and 9 females, aged from 3 months to 25 years with the average of 51.9 months. 14 cases were si n gle eye pathogenesis, 2 cases were binocular pathogenesis. Of the 16 eyes, 3 had anterior PHPV, 13 had components of both anterior and posterior disease. In addition, 10 eyes with cataract, 7 eyes with posterior synechia, 5 eyes with shallo w anterior chamber, 3 eyes with bandshaped degeneration of cornea, 1 eye with corneal opacity, 2 eyes contractive retinal detachment, 1 eye with rhegmatogenous retinal detachment. The visual acuity was light sensation, hand move, counting f ingers/10cm and 002 in 1 eye respectively. 12 eyes can not meet visual inspection, the reflection of b light was not obvious.13 eyes underwent lensectomy and anterior vitrectomy, 1 eye was implanted intraocular lens, 3 eyes with retin al detachment underwent lensectomy, vitrectomy, photocoagulation, gas tamponade and scleral buckling. Follow-up ranged from 6 months to 4 years (mean 15.3 months). Results After surgery, all 16 eyes had normal intraocular pressure and anterior chamber, retinal attachment; two eyes achieved a visual acuity of 10/100 and 20/ 100; 8 patients have the reflection of b light who once didnprime;t meet visual inspection; the visual acuity in 6 patients below counting fingers. Conclusions Surgical treatment of PHPV can prevent future glaucoma and he morrhagic complications. It is useful to win functional visual acuity if it combined with amblyopia training after surgery. （Chin J Ocul Fundus Dis，2008，24：210-212）
Objective To investigate the inhibitive effect of E2F decoy oligodeoxynucleotides (E2F decoy ODNs) on cultured human retinal pigment epithelial (HRPE) cells.Methods E2F decoy ODNs or scramble decoy ODNs at varied concentrations were put into the HRPE cells mediated by lipofectamineTM2000. The proliferative activity of HRPE was detected by methythiazolyl-terazollium assay, and the competitive combinative activity of E2F decoy ODNs and transcription factor E2F was detected by electrophoresis mobility-shift assay. Results The proliferation of HRPE was inhibited markedly by E2F decoy ODNs at the concentration of 0.2 μmol/L (P=0.002) in a dose-dependent manner but not by scrambled decoy. The results of electrophoresis mobility-shift assay showed that the combinative activity of transcription factor E2F was abolished completely by E2F decoy ODNs. Conclusions E2F decoy ODNs may sequence-specifically inhibit the combinative activity of transcripti on factor E2F,and inhibit the proliferation of HRPE cells.(Chin J Ocul Fundus Dis，2004，20：182-185)
Objective To analyze the clinical risk factors of the occurrence of severe proliferative vitreoretinopathy (PVR) after scleral reattachment surgery. Methods A total of 4031 eyes of 4031 consecutive patients with reghmatogenous retinal detachment (RRD) and PVR (grade C1 or less), on whom the scleral buckling was performed, were retrospectively studied. Twenty-two clinical charac teristics of the patients (including the ocular tension, condition of lens and vitreous, characte ristics of retinal detachment, whether or not with choroidal detachment, et al) were recorded.In 4031 patients, 2660 were followed up for more than 3 months, and 72 (in PVR group) of the 2660 patients underwent the second surgery (vitre oretinal surgery) because of the occurrence of postoperative seve re PVR; in the other 2588 patients, 72 (72 eyes) with retinal reattachment for more than 3 months were selected randomly as the control. The data were analyzed in SPSS (10.0) software. Results Logistic regression analysis revealed that the significant risk factors for PVR were incomplete posterior vitreous detachment ( P＜0.001), intraocular pressure lt;7 mm Hg（1 mm Hg=0.133 kPa, P＜0.002）, and large retinal tear (gt;2 DD,P＜0.005). Conclusion Incomplete posterior vitreous detachment, intraocular pressure lt;7 mm Hg and large retinal tear of the patient with RRD may be the major risk factors for PVR. (Chin J Ocul Fundus Dis，2003，19：141-143)
Objective To evaluate the effect of vascular endothelial cell growth factor (VEGF) antisense oligodeoxynucleotides (ASODNs) on the expression of VEGF in rats with oxygen-induced retinopathy. Methods Thirty newborn Sprague-Dawley (SD) rats were randomly divided into 3 groups:normal control group, disposal group and non-disposed group, The animal models with oxygen-induced proliferative retinopathy were established by raising the rats in hyperoxic environment. Retrobulbar injection was performed with VEGF ASODNs or normal saline on the rats in 3 groups respectively. The intraocular tissues (all the tissues except the cornea, sclera, and lens) and serum were collected, and the expressions of VEGF were determined by using competitive enzyme immunoassay.Results The expressions of VEGF in intraocular tissues of rats in disposal group were significantly lower than those in non-disposed group (P＜0.05), and there was no statistical difference between the disposal and normal control group (P＞0.05). There was no significant difference of the expressions of VEGF in serum of rats between the disposal and non-disposed group (P＞0.05), which were both lower than those in the normal control group (P＜0.05). Conclusion VEGF ASODNs could significantly inhibit the expression of VEGF in intraocular tissues. (Chin J Ocul Fundus Dis，2003，19：172-174)
Objective To evaluate the anatomical and functional results of retinotomy in treatment of complicated retinal detachment. Methods Twenty-three eyes were treated with retinectomy during vitrectomy for complicated retinal detachment with proliferative vitreoretinopathy when complete reattachment of retina was not obtained despite careful mambrane peeling. After released the peripheral vitreoretinal contraction or pulled subretinal membranes, perfluorocarbon liquid injection, laser retinopexy and silicone oil tamponade were performed. Retinotomy size ranged from 30-degree to 360-degree (average 132-degree). Results Retinal attachment were obtained in all of the operated eyes at the end of the operation. Silicone oil was removed from 15 eyes (65．0%) within 3～11 months postoperatively. After a minimum follow-up of 6 months, the retinae were completely attached in 17 eyes ( silicone oil was not removed in 4 eyes ) and visual acuity of 0.02 or better was obtained in 11 eye (48．0%). Recurrent retinal detachment occurred in 2 eyes in which the silicone oil had been removed. The major complications were recurrence of the proliferation in 6 eyes (26．0%) and hypotony in 3 eyes (13．0%). Conclusion Retinotomy is beneficial to reattach the retina for eyes with advanced proliferative vitreoretinopathy in seemin gly inoperable cases. (Chin J Ocul Fundus Dis,2001,17:87-89)
ObjectiveTo observe the expression of heat shock protein 47 (HSP47) and transforming growth factor-β2(TGF-β2) in vitreous specimens and epiretinal membranes of patients with proliferative vitreoretinopathy diseases. MethodsVitreous specimens and epiretinal membranes were obtained from 48 patients (48 eyes) with proliferative vitreoretinopathy (PVR) and 50 patients (50 eyes) with proliferative diabetic retinopathy (PDR). Vitreous specimens and internal limiting membranes were collected from 20 patients (20 eyes) with idiopathic macular hole (IMH) as control group. The expression of HSP47 and TGF-β2 in the vitreous specimens was evaluated using enzyme linked immunosorbent assay. The expression of HSP47, TGF-β2, typesⅠandⅢcollagen in epiretinal membrane and internal limiting membrane specimens were observed for immunohistochemical staining method. The correlation between the positive expression of HSP47 and TGF-β2, typesⅠandⅢcollagen in epiretinal membrane specimens of patients with PVR and PDR were analyzed. ResultsThe expression of HSP47 in vitreous specimens of patients with PVR, PDR and IMH were (212.35±23.32), (231.30±26.79), (171.06±28.91) pg/ml, respectively. The expression of TGF-β2 in vitreous specimens of patients with PVR, PDR and IMH were (1919.96±318.55), (1939.39±177.57), (1194.61±234.20) pg/ml, respectively. The expression of HSP47, TGF-β2 in the vitreous specimens of patients with PVR and PDR were significantly increased compared with patients with IMH and the difference was statistically significant (F=12.952, 34.532;P < 0.01). The epiretinal membrane of patients with PVR and PDR showed markedly increased expression of HSP47, TGF-β2, typesⅠandⅢcollagen in the cytoplasm and extracellular matrix. The expression of HSP47 and typeⅢcollagen was negative and the expression of TGF-β2 was weakly positive and the expression of typesⅠcollagen was positive in internal limiting membrane of patients with IMH. The expression of HSP47, TGF-β2, typesⅠandⅢcollagen in the epiretinal membrane of patients with PVR and PDR were significantly increased compared with patients with IMH and the difference was statistically significant (F=13.469, 18.752, 12.875, 20.358; P < 0.01). The expression of HSP47 was positively correlated with the positive expression of TGF-β2, typesⅠandⅢcollagen in epiretinal membrane specimens of patients with PVR (r=0.475, 0.556, 0.468; P < 0.05) and PDR (r=0.484, 0.589, 0.512; P < 0.05). ConclusionsThis study showed increased consistent expression of HSP47 and TGF-β2 in vitreous and epiretinal membrane specimens of patients with PVR and PDR. Both HSP47 and TGF-β2 were expressed in the cytoplasm and extracellular matrix. HSP47 and TGF-β2 may be involved in the pathological process of PDR and PVR by promoting collagen synthesis.
Proliferative vitreoretinopathy (PVR) is a common complication and major cause of blindness of ocular trauma. Many cytokines, including vascular endothelial growth factor (VEGF) and platelet-derived growth factor (PDGF), participate in the process of the pathogenesis of traumatic PVR. VEGF competitively inhibits binding of PDGF to its receptor (PDGFRα), enables indirect activation of PDGFRα by non-PDGF ligands, resulting in reduced p53 expression, cell proliferation and migration, which is a key point in the pathogenesis of traumatic PVR.