LXHY formula inhibits choroidal neovascularization development via inhibiting the recruitment and adhesion of BMCs to the retina

Objective: The objective of this study is to investigate the inhibitory effect of LXHY, a Chinese medicine compound formula, on choroidal neovascularization (CNV) and to find the possible working mechanism. Methods: CNV was induced in C57BL/6 mice by krypton laser and bone marrow-derived cells (BMCs) isolated from enhanced green fluorescent protein (EGFP) transgenic mice were injected through tail vein 0.5–1 h after the laser surgery. The BMC-treated mice were randomly divided into two groups gavaged with either distilled water (DW group) or LXHY formula solution from day 1 after laser surgery. On days 7, 14, and 28 after treatment, histopathologic examination, fundus fluorescein angiography, and choroidal flatmount assay were performed to measure the CNV severity and BMC recruitment. CXCR4 levels in peripheral blood were measured by enzyme-linked immunosorbent assay. Stromal cell-derived factor-1α (SDF-1α), vascular cell adhesion molecule-1 (VCAM-1), and intercellular adhesion molecule-1 (ICAM-1) were detected by immunofluorescent staining. Results: On days 7 and 14 after treatment, CNV lesions in the LXHY-treated mice showed less recruitment of BMCs and were smaller in size compared to DW-treated mice. Histological examination also confirmed less severe CNV lesions in the LXHY group. CXCR4 levels in peripheral blood in the LXHY group were less than that of DW group on days 7 and 14. Moreover, the expression levels of SDF-1α, ICAM-1, and VCAM-1 at the lesion sites in the LXHY group were lower compared with the DW group. Conclusion: This experiment indicated that LXHY formula could inhibit CNV formation and development, probably by inhibiting the recruitment and attachment of BMCs into CNV area