Effect Of NF-kappa B Signaling Activation On Experimental Ocular Neovascularization

Purpose.Anti-VEGF treatment is effective in only part of patients with ocular neovascularization(NV)and has certain side effect.NF-?B signaling participates in regulating tumor angiogenesis and metastasis.However,its mechanism of action in ocular NV remains unclear.Therefore,this study investigated the role of NF-?B in regulating ocular angiogenesis and the underlying mechanism in mouse models.Methods.1.The retinas from oxygen-induced retinopathy(OIR)mice treated with pyrrolidinedithiocarbamate(PDTC)or PBS were used to carry out immunofluorescence,Western blot and retinal flat-mount,and then to examine activation of NF-?B signaling and influence on retinal neovascularization(RNV).2.The retinas from OIR mice and retinal/choroidal complex from laser-induced choroidal neovascularization(CNV)mice treated with PDTC or ATN-161(the antagonist of integrin ?5?1)to detect cell apoptosis of CNV and RNV by Terminal deoxynucleotidyl transferase d UTP nick-end labeling(TUNEL),expression of matrix metalloproteinase-2/9(MMP-2/9)and macrophage(Mf)polarization-associated genes by RT-PCR and Western blot.Results.The expression of phosphorylated I?B?(p-I?B?)and p-p65 increased in OIR mice.Inhibiting NF-?B signaling activation by PDTC significantly reduced RNV and expression of integrin ?5?1 and MMP-2/9.Blocking integrin ?5?1 by ATN-161 strongly inhibited expression of MMP-2/9 and RNV.PDTC and ATN-161 promoted cell apoptosis of NV in mice with OIR or CNV.The expression of M1 Mf associated cytokines decreased and M2 associated cytokines increased in OIR mice treated with either PDTC or ATN-161.Conclusions.In ocular NV,NF-?B signaling activation via integrin ?5?1 promoted expression of MMP-2/9.Blocking activation of NF-?B and expression of integrin ?5?1 promoted cell apoptosis of ocular NV and polarization of M1 Mf to M2 Mf.