Impact of evodiamine on retinal injury in diabetic rats by regulating cyclic adenosine monophosphate/protein kinase A signaling pathway / 眼科新进展

ABSTRACT

Objective To investigate the effect of evodiamine(EVO)on retinal injury in diabetic rats by regulating the cyclic adenosine monophosphate(cAMP)/protein kinase A(PKA)signaling pathway.Methods Totally 96 Sprague-Dawley rats(192 eyes)were divided into the negative control(NC)group,Model group,low-dose EVO(EVO-L)group,medium-dose EVO(EVO-M)group,high-dose EVO(EVO-H)group,calcium dobesilate(CD)group,SQ22536 group and EVO-H+SQ22536 group,with 12 rats in each group.Rats in the NC group were intraperitoneally injected with physiological saline instead of streptozotocin,and diabetic retinopathy models were established in all other groups.After successful mod-eling,the drug was administered once a day for 4 weeks.The blood glucose level of rats in each group was measured by blood glucose meter;HE staining was applied to detect the pathological changes of the retina of rats;TUNEL staining was adopted to detect the apoptosis of ganglion cells in the retina of rats;the levels of superoxide dismutase(SOD),malondial-dehyde(MDA),tumor necrosis factor-α(TNF-α),interleukin(IL)-6 and cAMP in the retina of rats were detected;West-em blot was used to detect the protein expressions of Bcl-2 associated X protein(Bax),P53 and phosphorylated protein ki-nase A(p-PKA)in the retina of rats.Results Compared with the NC group,the pathological injury of the retina in the Model group was more serious;the blood glucose,apoptosis rate of retinal ganglion cells,MDA,TNF-α,IL-6,Bax and P53 protein expressions increased,and the SOD,cAMP and p-PKA/PKA protein expression decreased,with statistically significant differences(all P＜0.05).Compared with the Model group,the pathological injury of the retina was relieved,the blood glucose,apoptosis rate of retinal ganglion cells,MDA,TNF-α,IL-6,Bax and P53 protein expressions decreased,and the SOD,cAMP and p-PKA/PKA protein expression increased in the EVO-L group,EVO-M group,EVO-H group and CD group,with statistically significant differences(all P＜0.05).Compared with the Model group,the retinal tissue of the SQ22536 group was severely damaged,the blood glucose,apoptosis rate of retinal ganglion cells,MDA,TNF-α,IL-6,Bax and P53 protein expressions increased,and the SOD,cAMP,p-PKA/PKA protein expression decreased,with statistically significant differences(all P＜0.05).Compared with the EVO-H group,the EVO-H+SQ22536 group showed more serious pathological injury of retinal tissue,increased blood glucose,apoptosis rate of retinal ganglion cells,MDA,TNF-α,IL-6,Bax and P53 protein expressions,and decreased SOD,cAMP and p-PKA/PKA protein expression,and the differences were statistically significant(all P＜0.05).Conclusion EVO may alleviate retinal injury in diabetic rats by activating the cAMP/PKA signaling pathway.