The Effects Of Nano-Silver Graphene-Oxide Loaded Gel Lacrimal Stent On The Healing Process Of Rabbits With Lacrimal Canal Injury

Objective: To observe the effect of nano-silver graphene oxide loaded lacrimal stent on the healing process of rabbit lacrimal canalicular injury,and to detect the expression of inflammatory cells,apoptosis and ?-SMA in lacrimal canalicular tissue.It provides a new theoretical basis for clinical treatment of lacrimal duct injury and lacrimal duct obstructive disease.Methods: Thirty-five New Zealand white rabbits weighing 2.0-2.5 kg were selected from healthy males.Five randomly selected blank controls(group A),30 rabbits were injected with 4ml of fosfomycin sodium and glucose hardener for 7 consecutive days to establish a rabbit tear canal injury model.In group A was injected with the same amount of PBS.The successful rabbits were randomly divided into groups B,C,D,E,and F.Lacrimal stents were made using the 3D printing method,and lacrimal stents of uniform length and thickness were selected.Group B was hydrogel and group C nanometers.Silver,Group D nano silver-graphene oxide,E drug group(nano-silver graphene levofloxacin drug-loaded gel),F negative control.All groups B,C,D and E were implanted with corresponding lacrimal duct plugs on the 7th day after the model was implanted.The rats in group F were removed immediately after implantation.Three days after the implantation of the lacrimal duct stent,the plastic shell was removed and re-implanted.The tear secretion test and corneal fluorescein staining examination were performed on the 0th,7th,and 14 th days of the experiment,and lacrimal duct tissues were taken for hematoxylin-I.Hematoxylin-eosin staining(HE staining)and apoptosis of TUNEL cells were used to evaluate the effect of nano-silver graphene oxide loaded lacrimal stents on the inflammation of lacrimal passages and the difference in tissue structure between rabbits with lacrimal duct injury.Immunofluorescence was used to detect the content of ?-SMA in lacrimal passages of rabbits,which indirectly reflected the effects of lacrimal stents loaded on the formation of scars and fibrosis in rabbit canalicular tissues.Result: 1.The length and thickness of lacrimal stents were uniform in all groups,and the difference was not statistically significant.2.After 7 days of modeling,the amount of lacrimal secretion decreased compared with that of the blank group.Corneal fluorescein staining was positive.The amount of lacrimal secretion after lacrimal stent implantation gradually increased.After 7 days of implantation,the drug-loading group increased significantly,the amount of tear secretion was comparable to that of the blank group.There was no significant staining of the cornea.3.HE staining results showed that: normal rabbit latrine tissue is divided into two layers,epithelial and subepithelial stromal layer,the epithelial layer is composed of multi-layered squamous epithelial cells,arranged neatly,the stromal layer organization structure is loose,normal rabbit lacrimal canaliculi No inflammatory cell infiltration was observed in epithelial tissue.On the 7th day after modeling,mucosal epithelial folds,edema,structural disorder,epithelial cell integrity and continuity were disrupted,and a large number of inflammatory cells infiltrated in both epithelial and stromal layers.After implanted for 7 days,the morphology of the epithelial tissue of the drug-loaded group basically recovered,and the inflammatory cells were significantly reduced compared with other groups.4.TUNEL experimental results showed that nano-silver graphene oxide levofloxacin drug-loaded lacrimal duct can effectively inhibit the apoptosis of rabbit lacrimal canal injury tissue5.The results of ?-SMA immunofluorescence showed that there was no expression of ?-SMA in normal lacrimal duct tissue.The expression of ?-SMA was up-regulated after lacrimal canal injury.After implanted with lacrimal duct stent for 7 days,?-SMA expression in drug-loaded group was higher than that of hydrogel.Nano-silver,nanosilver graphene oxide and negative control groups were significantly.Conclusion:1.Fosfomycin glucose production tear tube damage model has a high rate of molding,good stability,simple operation,is a reliable method of modeling.2.Nanosilver graphene laden drug loaded gel lacrimal stent has a good sustained release of drugs,can better reduce the inflammatory response,inhibit rabbit fibrosis of canalicular tubules,in the promotion of lacrimal canal injury healing process can potentially inhibit Lacrimal stenosis.3.Nano-silver graphene oxide loaded gel lacrimal stent has little irritative effect on the ocular surface and does not damage the cornea.It is a safe and effective method for treating lacrimal duct obstructive diseases.