ABSTRACT
Objective To explore the effect of Shuanglu Tongnao Formula on neuronal ferroptosis in ischemic stroke rats and its regulatory mechanism on the silent information regulator 2 homolog 1(SIRT1)/nuclear factor erythroid 2-related fac-tor 2(Nrf2)/glutathione peroxidase 4(GPx4)signaling pathways.Methods Twenty rats were selected as sham operation group by the random number table method,and the remaining seventy rats were made ischemic stroke rat models by the middle cerebral artery occlusion method.The rats that had been successfully modeled were randomly divided into the model control group,Shuanglu Tongnao formula group,Shuanglu Tongnao formula+SIRT1 inhibitor group(Shuanglu Tongnao formula+EX527 group),with 20 rats in each group.After 14 days,the rats were scored for neurological injury;TTC staining was applied to detect the area of cerebral infarction in rats;HE staining was applied to detect pathological changes in rat brain tissue;Nissl staining was applied to detect the number of neurons in rat brain tissue;the kit was applied to detect the levels of ferri ion(Fe2+),superoxide dismutase(SOD),glutathione(GSH),and malonaldehyde(MDA)in rat brain tissue;immunohistochemistry was applied to de-tect the positive expression of acyl-CoA synthetase long-chain family member 4(ACSL4),transferrin receptor(TFR),and ferritin heavy polypeptide 1(FTH1)proteins in rat brain tissue;Western blotting method was applied to detect the expression of SIRT1,Nrf2,GPx4,and cystine/glutamate antiporter solute carrier family 7 member 11(SLC7A11)proteins in rat brain tissue.Results Compared with the sham operation group,the neurological deficit score,cerebral infarction area,the contents of Fe2+and MDA,and the protein expressions of ACSL4 and TFR in model control group were increased(P<0.05);the number of neurons,the con-tents of SOD and GSH,the protein expression of FTH1,SIRT1,Nrf2,GPx4,and SLC7A11 were all reduced(P<0.05).Compared with the model control group,the neurological deficit score,cerebral infarction area,the contents of Fe2+and MDA,and the protein expression of ACSL4 and TFR in the Shuanglu Tongnao formula group were reduced(P<0.05),and the number of neurons,the contents of SOD and GSH,the protein expressions of FTH1,SIRT1,Nrf2,GPx4,and SLC7A11 are all increased(P<0.05).The results of the SIRT1 inhibitor supplementation experiment showed that the SIRT1 inhibitor reversed the inhibitory effect of Shuan-glu Tongnao formula on neuronal ferroptosis,while also inhibited the expression of Nrf2 and GPx4(P<0.05).Conclusion The Shuanglu Tongnao formula may inhibit neuronal ferroptosis in ischemic stroke rats by activating the SIRT1/Nrf2/GPx4 signa-ling pathway.
ABSTRACT
AIM To investigate the effects of Zhuangyao Shuanglu Tongnao Formula on neuronal apoptosis in rats with cerebral ischemia-reperfusion injury based on the study of oxidative stress and inflammatory response.METHODS The rats were randomly divided into the sham operation group,the model group,the edaravone group(3.0 mg/kg),the low,medium and high dose groups(9.0,18.0,36.0 g/kg)of Zhuangyao Shuanglu Tongnao Formula,with 18 rats in each group.The middle cerebral artery occlusion/reperfusion was conducted by thread embolism method to simulate cerebral ischemia reperfusion injury in rats followed by 6 days corresponding drugs administration.Subsequently,the rats had their neurological function deficit scored by Zeal Longa scoring method;their sizes of cerebral infarction areas measured by TTC staining;their pathological damage and apoptosis of neurons in hippocampal CA1 area of ischemic penumbra of the brain tissue detected by HE staining and TUNEL staining;their SOD activity and levels of GSH,MDA,IL-6,IL-1β,TNF-α in brain tissue detected by kits;and their protein expressions of Bax,Bcl-2,caspase-3,cleaved-capase-3,TLR4,NF-κB p65,Nrf2,HO-1 in rat brain tissue determined by Western blot.RESULTS Compared with the model group,the groups intervened with edaravone,medium and high dose of Zhuangyao Shuanglu Tongnao Formula displayed improvements in the scores of nerve function defects,the rate of cerebral infarction,the rate of neuronal apoptosis,the levels of IL-6,IL-1β,TNF-α and MDA in the ischemic penumbra of brain tissues,the protein expressions of Bax and TLR4,the ratio of cleaved-capase-3/caspase-3 and p-NF-κB p65/NF-κB p65(P＜0.05),the levels of GSH,the activity of SOD and the protein expressions of Bcl-2,Nrf2 and HO-1(P＜0.05).CONCLUSION Being an inhibitor of oxidative stress and inflammatory response,Zhuangyao Shuanglu Tongnao Formula can alleviate brain injury in rats with cerebral ischemia reperfusion injury through the inhibition of neuronal apoptosis and improvement of neural function mediated by the inhibition of TLR4/NF-κB signal pathway and activation of Nrf2/HO-1 signal pathway.