AIM: To observe the inhibitory effects of formation of choroidal neovascularization(CNV)in rats induced by laser by naringenin and complex of copper(II)with free ligand.

METHODS: A total of 24 male Brown-Norway rats were selected including 18 rats as CNV model and 6 as normal comparison. A total of 18 model rats were divided randomly into control, naringenin and its complexes of copper group with 6 rats in each group. Naringenin and its complexes \〖20mg/(kg·d)\〗 were given once-daily through intraperitoneal(i.p.)injection after laser treatment for 30d in two experimental groups, respectively. Complex samples of retina, choroid membrane and sclera in each group were taken after 30d of the establishment of animal model. The sizes of CNV lesions were observed under fluorescence microscope. Samples of choroid in each group were taken. The expression of protein and mRNA of COX-2, VEGF, PI3K, MAPK, MMP-2 and MMP-9 were examined by Western blotting and RT-PCR method at 30d.

RESULTS: The animals treated with naringenin and its complexes of copper showed significant decrease in their average CNV sizes, compared with that of the vehicle-treated animals(P<0.01), especially with naringenin's and its complexes of copper group. Compared with the vehicle-treated animals, the mRNA and protein expressions of VEGF, COX-2 and so on were significantly higher than that in the model control group(P<0.01). The expression of gene and protein in each experimental group both decreased when compared with model group. Except PI3K, MMP-9, the reduction degree in the naringenin and its complexes of copper group were larger than that in the single naringenin group(P<0.05). The differences of reduction degree were statistically significant.

CONCLUSION: These results indicate that the biological activity of naringenin can be enhanced by the formation of its complexes, and that complexes of naringenin have stronger inhibition effect on the formation of CNV in rats induced by laser.