Intravitreal injection of antiangiogenic agents is widely used to treat retinal vascular disease. This therapy can induce regression of neovascular vessels; reduce intraocular inflammation and retinal vascular permeability, and control macular edema. However the action period of these agents is short, and thus this therapy need repeated injections which cause higher operation risk and cost. Retinal laser photocoagulation therapy can close retinal capillary non-perfusion area and neovascular vessels, reduce macular edema caused by vascular leakage. However, as its therapeutic effect is based on the destruction of the retinal tissues in the lesion area, this therapy need longer time to show its effects. When the disease is controlled by this method, it may already induce some structural irreversible damages to the retina, especially the macular. This is why the visual acuity is not satisfactory in some patients, even though the disease get controlled, macular edema gets disappeared and anatomical structure of retina get improved. Properly evaluating all the pros and cons of retinal photocoagulation and intravitreal injection of antiangiogenic agents, will allow us to explore a better way to combine these two therapies to treat retinal vascular diseases.
Objective To investigate the effects and mechanism of curcumin on the retinal neovasularization in mice with oxygeninduced retinopathy (OIR). Methods A total of 72 C57BL/6J mice were divided into normal, OIR model, vehicle control [dimethyl sulphoxide (DMSO)], and curcumin group (100, 50, and 10 mg). The mice in normal group lived in normoxia condition; OIR model was set up according to standard methods in the literature. Five days after OIR establishment, the mice in curcumin group received an intraperitoneal (IP) injection of 0.1 ml curcumin (100, 50, and 10 mg), and the mice in DMSO group received an IP injection of 0.1 ml 1permil; DMSO. All of the mice were executed at the age of postnatal day 17 (P17) and the eyeballs were collected. Endothelial cell nuclei breaking through the internal limiting membrane were counted after stained with hematoxylin and eosin (HE). The expression of vascular endothelial growth factor-A (VEGF-A), vascular endothelial growth factor receptor-2 (VEGFR-2), endostatin (ES), and phosphorylated p38 mitogen-activated protein kinase (p-p38MAPK) in the retina in each group were measured by real-time polymerase chain reaction (RT-PCR) and Western blot methods.Results Compared with the normal group, retinal neovascularization was found in OIR model group (P<0.05). The number of endothelial cell nuclei was 46.00plusmn;16.00 in OIR model group and 0.17plusmn;0.41 in normal group (P<0.05). The expression of VEGF-A, ES, and p-p38MAPK in 100 mg curcumin group differed statistically from which in 50 and 10 mg curcumin group (P<0.05). The expression of VEGFR-2 was same in the three curcumin groups (P>0.05). Conclusion Curcumin can inhibit the formation of retinal neovascularization; the mechanism may be associated with inhibiting the expression of VEGFA and VEGFR-2, increasing the expression of ES, and inhibiting the p38MAPK signal transduction pathway.
Up-regulation of vascular endothelial growth factor (VEGF) is demonstrated to be a key role in formation process of intraocular neovascularization. Anti-VEGF treatment is the breakthrough of intraocular neovascular diseases therapy. Intrav itreal injection of antineovascularization drug looks to be an effective method on ocular neovascular diseases which with the advantages of good biocompatibility, low prices and longer intravitreal half-time etc. However, at present, it lack of multi-center study; the long-term efficacy and the systematic safety needs the further clinical verification. Various types of CNV showed the different therapeutic reactions to either PDT or Anti-VEGF agent, the treatment methods for exudative AMD include laser, PDT, and drug like Triamcinolone Acetonide,several anti-VEGF preparations. Therefore, understanding the pathogenesis of neovascular AMD and choosing a reasonable therapeutic methods are necessary. We should try to explore a safe, effective, economic, new approach. (Chin J Ocul Fundus Dis,2008,24:157-159)
Objective To invesitgate the influence of recombinant adenovirus vector of human pigment epithelium-derived factor(AV-hPEDF)on retinal new vessels mediated by recombinant adenovirus vector. Methods Twenty 7-days-old Sprague-Dawley (SD) rat were divided into two groups randomly after the establishment of retinal neovascularization model. At postnatal 14 day, they were accepted intravitreal injection with blankadenovirus-vector (AV-Blank group) and adenovirus-vector PEDF(AV-PEDF group) respectively. The retinal vascular endothelial cells were counted, the PEDF mRNA and protein expression in retina and vitreous were determined by reverse transcriptionpolymerase chain reaction (RT-PCR) and immunohistochemistry. Results After injection with medicine, the number of RNV was decreased obviously in AV-PEDF group(t=42.009,Plt;0.001);the protein expression of retinal PEDF was increased obviously in AV-PEDF group(t=36.638,Plt;0.001); the PEDF mRNA expression in vitreous was also increased obviously in AV-PEDF group (t=9.128,Plt;0.001). Conclusion Recombinant Adenovirus vector mediated PEDF can raise the PEDF expression in the retinal and vitreous neovascularized tissues in rat, which suggested that the expression of PEDF may be related to inhibition and reduction of RNV.
Objective To investigate the therapeutic efficacy of transpupillary thermal therapy (TTT) for age-related macular degeneration (AMD) accompanied with subfoveal choroidal neovascularization (CNV). Methods Fifty-one eyes of 47 patients whose illness had been diagnosed as AMD by fundus fluorescein angiography (FFA) and indocyanine green angiography (ICGA) were treated with diode 810 laser. There are 42 eyes of 39 patients had occult CNV and 9 eyes of 8 patients had classic CNV, and the average visual acuity in their fist diagnosis was 0.12. According to the focus size, the diameters of beam spot varied from 0.8, 1.2, 2.0, and 3.0 mm; and the power was 120, 160, 260 and 360mW correspondingly, with the duration of 60 seconds. The follow-up examination was performed once a month after the treatment, and repetitious treatment would be taken once to thrice if necessary. The follow-up period was 3~33 months with the mean of 10 months. Visual acuity, haemorrhage in ocular fundus, absorption of exudation, and the closure of CNV were examined in the follow-up examination. Results No immediate decrement of visual acuity or any other discomforts were found in all of the treated eyes soon after the treatment. The average visual acuity of 51 eyes was 0.16 in the last diagnosis, which remained no change in 68.62%; increased in 23.53% and decreased in 7.84% compared with that in the first diagnosis. The results of FFA and ICCG demonstrated that at the 3rd months after the treatment, the closure rate was 42.86% in occult CNV and 22.22% in classic CNV; and at the 6th month, the closure rate was 73.81% in occult CNV and 66.67% in classic CNV. The results of ophthalmoscopy showed that at the 3rd month after the treatment, partial or complete absorption of hemorrhage and/or exudates with various thickness of organized scarring tissue was found in 42 eyes with occult CNV; decrement of hemorrhage and exudates was observed in 7 out of 9 eyes with classic CNV; and new hemorrhage occurred in 1 eye. At the 6th month, in 27 eyes with occult CNV, new hemorrhage occurred in 3 including 2 eyes with occult CNV, new hemorrhage occurred in 3 including 2 eyes with faster absorption and remaining unchanged for 12 months; in 5 eyes with classic C NV, new hemorrhage occurred in 2, which was absorbed after treated again and remained stable in the 16-month followed-up. In 19 eyes with occult CNV which had been followed up for more than 6 months, hemorrhage disappeared in 5 and new hemorrhage occurred in 5. In the followed-up over 6 months, new hemorrhage occurred in 8 eyes with the recurrent rate of 15.6%. Conclusion TTT is effective for AMD with either classic or occult CNV. In the long-term followed-up, CNV recurs in 15.6% of the treated eyes which may be improved after the further treatment. (Chin J Ocul Fundus Dis,2004,20:280-284)