The Research On The Neuroprotective Effect Of Piezo1 On Optic Nerve In Acute Intraocular Hypertension Glaucoma Model Mice

Objective: To explore whether mechanical sensitivity ion channel protein Piezo1 is involved in the retina microglial cells activation of acute high intraocular pressure model rats.To Clear,the neuroprotection role of regulating Piezo1 on microgliamediated retina nerve inflammation reaction of acute high intraocular pressure model ratsMethods: Selected 24 male C57BL/6 mice,age 6～8 weeks,weight 20～25g.The experimental mice were randomly divided into blank Control(Control)group 、 acute high intraocular pressure mold 1d(1d)group、acute high intraocular pressure mold3d(3d)group、acute high intraocular pressure mold 7d(7d)group.Then,the frozen section of the retina HE dyeing was used to detect retinal thickness.Immunofluorescence staining to detect the activation degree of the microglia(Iba1 marker).Enzymelinked immunosorbent experiment method(Elisa)was used to detect the secretion level of the retinal tumor necrosis factor-alpha(TNF-α)、 Interleukin1-beta(IL-1β)and brain-derived neurotrophic factor(BDNF).Immunofluorescence co-localization was used to detect the expression position of Piezo1 in retina microglia(Iba1 marker).Then we chose 3d as a time node for further experiments according to the degree of microglia-mediated inflammatory reaction.Selected 36 male C57BL/6 mice,age6～8 weeks,weight 20～25g.The experimental mice were randomly divided into the Control group、3d group、3d+ inhibitor group(3d+ GsMTx4)、the inhibitor group(GsMTx4 group)、3d+ activator group(3d+Yoda1)、 the activator group(Yoda1group).Western blot was used to detect retina Piezo1 and Iba1 protein expression levels.Elisa test was used to detect the secretion level of the Interleukin1-beta(IL-1β).TUNEL staining was used to detect the retinal cell apoptosis.Retina patch was used to count retina ganglion cells(Brn3a marker).Results: Immunofluorescence results show ed that the retinal microglial cells were activated under acute high intraocular pressure.Elisa tests showed,compared with the control group,the production of inflammatory cytokines TNF-α and IL-1β was the most at the third day after acute high intraocular pressure model building up(P<0.01).The production of BDNF was the most at the first day after acute high intraocular pressure model building up,and then gradually reduced(P<0.01).Immunofluorescence co-localization results showed that Peizo1 protein expressed in retinal microglial cells and the expression was positively associated with the degree of microglia activation.After the intervention of Piezo1 nonspecific inhibitor(GsMTx4),comparing with the 3d group,Piezo1(P<0.01)and Ibal(P<0.05)protein expression levels decreased and the production of IL-1βdecreased(P<0.05).After the intervention of Piezo1 specific activator(Yoda1),the Piezo1(P<0.01)protein expression levels increased and the Iba1(P>0.05)protein expression levels decreased.After the intervention of Piezo1 nonspecific inhibitor(GsMTx4),retinal apoptosis levels decreased(P<0.05)and the survival of retina ganglion cells increased(P<0.05).Conclusion: Mechanical sensitivity ion channel protein Piezo1 was involved in retina microglia activation under acute high intraocular pressure.It is expected to reduce the microglia-mediated inflammatory response and achieve protection for optic nerve by down-regulating the expression of the Piezo1 protein in retinal microglia.