ABSTRACT
AIM: To study the role and mechanism of curcumol in neovascularization induced by vascular endothelial growth factor(VEGF).METHODS: Human umbilical vein endothelial cells were cultured in vitro and treated with 50ng/mL VEGF and curcumol at different concentrations. Cell proliferation was detected by CCK-8 and EdU assay, the migration ability of cells was analyzed by Transwell assay, the angiogenesis ability of endothelial cells was analyzed by tube formation assay, and the change of Akt/mTORC1 signal pathway was detected by Western blot.RESULTS: CCK-8 results showed that the OD450 value of cells in 400 and 800 μmol/L curcumol+VEGF group was significantly lower than that in VEGF group(all P<0.01). EdU results showed that the rate of cell proliferation in 400 μmol/L curcumol+VEGF group was significantly lower than that in VEGF group(P<0.001). Transwell assay and the formation assay results showed that the number of migratory cells in 400 μmol/L curcumol+VEGF group was decreased, and the number and length of tube branches were also reduced compared with VEGF group(all P<0.001). Western blot results showed that curcumol significantly inhibited the expression of p-Akt and p-S6, which were downstream targets of Akt/mTORC1 pathway in cells.CONCLUSION: Curcumol can inhibit VEGF-induced cell proliferation, migration and tube formation of vein endothelial cells, and has a strong inhibitory effect on angiogenesis, which can be further studied in the treatment of ocular fundus neovascularization.
ABSTRACT
BackgroundChoriodal neovascularization is an important ocular manifestation of angiogenesis in eyes,which derives from the choroid capillaries.Recent studies have found that complement activation is playing a key role in the laser-induced CNV.Because of the key position of CFB in the alternative pathway,bytargeting CFB and blocking the alternative pathway may provide an approach to observe the role of this alternative pathway in the generation of CNV.Objective This study was to investigate the inhibitory effect of reconstructed complement factor B (CFB)-small interfering ribonucleicacid(siRNA)on choroidal neovascularization (CNV)and its mechanism. Methods Experimental CNV was induced by laser photocoagulation in 96 eyes of 48 clean Brown Norway rats.The rats were randomly divided into 4 groups.25,50 and 75 μg B factor siRNA were injected via caudal vein on 1 day,3,5 days after photocoagulation in different dose groups,and normal saline solution was injected at the same way in experimental control group.Other 12 normal rats were used as blank control group.Fundus fluorescein angiography(FFA) was performed on 3,7,14,21,28 days after injection of CFB-siRNA and CNV was scored.The expressions of vascular endothelial growth factor(VEGF) and factor Ⅷ in choroid were detected by immunochemistry.The expressions of CFB-siRNA,VEGF,transforming growth factor β2( TGF-β2 )proteins in choroid were determined using immunochemistry in 7,14,21,28 days,and the expressions of mRNA of CFB-siRNA,VEGF,TGF-β2 were examined by reverse transcription polymerase chain reaction(RT-PCR). ResultsFFA revealed that the CNV rates in various doses of CFB-siRNA groups were significant lower than those of experimental control group in various time points(P＜0.05),and those in 75 μg B factor siRNA were decreased in comparison with 25 μg B factor siRNA (P＜0.05).Immunochemistry showed that the intensities of the VEGF and factor Ⅶ expression in various doses of CFB-siRNA groups were weaker than the blank control group ( P ＜ 0.05 ).Compared with the control group,the expression of CFB reduced in 7 days,and then approached to the level near the control group.Fourteen to twenty-one days after injection of CFB-siRNA,VEGF and TGF-β2 depressions in different doses of CFB-siRNA groups were lower than blank control group( P＜0.05 ).CFB expression in choroid showed the lower levels in CFB-siRNA injection group compared with blank control group in from 7 through 21 days (P＜0.05).RT-PCR displayed the gradual increase of CFB mRNA and curve-like changes of VEGF and TGF-β2 with time prolong. Conclusions Recombinated CFB-siRNA can effectively inhibit laser-induced CNV by down-regulating the expression of VEGF and factor Ⅷ.Alternative pathway of complement plays an important role in the production of CNV.