Abstract:AIM: To explore the modulation effects of 17-β estradiol(E2)and tamoxifen(TAM)in chronic intraocular hypertension mouse model.
METHODS: We performed anterior chamber injection of magnetic beads to induced chronic ocular hypertension models. Adult C57BL/6 male mice were used in the experiments and randomly divided into four groups: control, Beads group, E2 group and E2+TAM group. The intraocular pressure(IOP)were measured by Tonolab tonometer. Central retinal thickness was evaluated by HE staining. Brn3a as a specific marker of retinal ganglion cells(RGCs), were stained and counted by immunohistochemistry(IHC)staining. Glial fibrillary acidic protein(GFAP)as a marker of proliferation of astrocytes, was quantified using western blotting.
RESULTS: The IOP level was significantly elevated after anterior chamber injection of magnetic beads compared to control group(P<0.05), while in E2 and E2+TAM group, the IOP levels were reduced(P<0.05 vs Beads group), especially in E2+TAM group in 2wk. The RGCs happened to degenerated in Beads group after 2wk, while the effects were reversed by E2+TAM(P<0.05). The central retinal thickness showed no significant statistical difference among the four groups after 2wk(P>0.05). The expression level of GFAP increased caused via beads injection, however, decreased in E2 and E2+TAM group(P<0.05).
CONCLUSION: E2 and E2+TAM could both effectively decrease the IOP level in chronic intraocular hypertension mouse model, increase the survival of RGCs from high intraocular pressure, suppress expression of GFAP, which indicated neuroprotective effects of E2 and TAM in glaucoma through an anti-inflammatory effects.