The Mechanism Of Pyroptosis Modulated By Resveratrol In Retinal Ischemic/reperfusion Injury

Retinal ischemia/reperfusion(I/R)is an important pathophysiological feature during the onset of glaucoma,which will result in the retinal inflammation and the death of retinal ganglion cells(RGCs).However,there is still a lack of effective targets to rescue RGCs.Pyroptosis is a proinflammatory programmed cell death,which may be involved in the retinal I/R injury-induced loss of RGCs.According to previous studies,resveratrol can effectively activate Sirt 1,has a strong ability of antiinflammation and is capable of providing neuroprotective effects in many degenerative retinal diseases.Nevertheless,whether resveratrol has an anti-pyrotic effect in retinal ischemia-reperfusion(I/R)is an outstanding issue.Objective: The purpose of the study is to investigate whether resveratrol is involved in the protective mechanism of RGCs through Sirt 1 mediating pyroptosis.Methods: Retinal ischemia-reperfusion(I/R)model in mice was constructed.In order to determine the peak of pyroptosis,the markers of pyroptosis were measured in1,2,and 3 days after retinal I/R injury.Through intraperitoneal injection to mice,the effects of resveratrol on pyroptosis,inflammasomes and the activation of retinal glial cells after I/R injury could be observed.Moreover,inducing the occurrence of pyroptosis in murine Müller glial cells(r-MC)via LPS was used to explore the effect of resveratrol on pyroptosis of r-MC in vitro.Results: After retinal I/R injury in mice in vivo,pyroptosis participated in the degenerative process of the retina and reached its peak 1 day after I/R injury.But the treatment of resveratrol alleviated the loss of RGCs after retinal I/R injury in mice,increased the thickness of the retina,decreased the number of terminal deoxynucleotide transferase d UTP nick end labeling(TUNEL)-positive cells,and upregulated the decreased expression of silent information regulator 1(Sirt 1).Resveratrol also inhibited the activation of caspase-1,the cleavage of GSDMD-N,the assembly of NLRP3/TMS1/ASC inflammasome,and the release of inflammatory cytokine IL-1β.Furthermore,after the treatment of resveratrol,the activation of retinal glial cells was obviously relieved.In vitro experiments,resveratrol mitigated pyroptosis of r-MC cells,saves cells from dying,reduced the release of lactate dehydrogenase(LDH),declined the number of propidium iodide(PI)-and TUNEL-positive cells,and restrained the pyroptosis-related NLRP3/GSDMD-N/TMS1/ASC/Caspase-1/IL-1β pathway.Discussions: The results of our work show that pyroptosis is key to the early stage of acute I/R retinal damage,which provides new evidence for the involvement of Müller glial cell activation in retinal inflammation.More importantly,our work demonstrates that resveratrol can protect retinal cells by inhibiting the activation of glial cells through Sirt 1 and thereby inhibiting the NLRP3 inflammasome-induced pyroptosis pathway.