Protective Effect Of Se-enriched Yeast Combined With Vitamin E On Doxorubicin-induced Cardiac Injury In Mice

Objective: Doxorubicin(DOX)is a broad spectrum antitumor drug commonly used in clinic,but its clinical application is limited due to its cardiotoxicity.In order to reduce the cardiotoxicity of adriamycin,the treatment of adriamycin cardiotoxicity has gradually received the attention of researchers in recent years,and there are few studies on the cardiotoxicity caused by selenium rich yeast combined with vitamin E.Therefore,the purpose of this study was to establish an animal model of adriamycin cardiac injury,to explore the protective effect and mechanism of se-rich yeast combined with vitamin E on adriamycin induced cardiotoxicity,and to provide experimental and theoretical basis for the treatment of adriamycin cardiotoxicity.Materials and Methods: forty 8-week-old male C57BL/6J mice were randomly divided into 5 groups after 1 week.(1)Normal control group(Con group,n=8): Mice in Con group were intragastric with equal volume normal saline once a day for 4 weeks,and intraperitoneally injected with equal volume normal saline once a week for 4 times.(2)Doxorubicin group(DOX group,n=8): MICE in DOX group were intragastric with equal volume normal saline,once a day,for 4 weeks,and intraperitoneal injection of 3 mg·kg-1DOX,once a week,for 4 times;(3)Doxorubicin + Selenium-rich yeast group(DOX+Se Y group,n=8): Mice in DOX+Se Y group were given intragastric administration of 100mg· kg-1SEY,once a day,for four weeks,and intraperitoneal injection of 3 mg·kg-1 DOX,once a week,for four times;(4)doxorubicin + selenium-rich yeast + vitamin E group(DOX+Se Y+VE group,n=8): mice in DOX+Se Y+VE group were given orally100mg· kg-1sey and 50 mg· kg-1ve,once a day,intraperitoneal injection 3 mg·kg-1 DOX,once a week,4 times in total;(5)Doxorubicin + sodium selenite group(DOX+Se group,n=8): MICE in DOX+Se group were given 0.2 mg· kg-1SEY orally,once a day,and intraperitoneal injection 3 mg·kg-1DOX,once a week,4 times in total.During the experiment,the general condition of mice was observed and recorded.Four weeks later,the mice were sacrificed,and the hearts were removed.The hearts were divided into two parts,one part of which was fixed in 4% paraformaldehyde fixative for 48 h,then paraffin embedding and HE staining were performed,and pathological damage of myocardial tissue in each group was observed.The other part was stored in the refrigerator at-80℃,and then protein western blot was used to detect the antioxidant SOD and GSH--Px,inflammatory factors NF‐κB and TNF‐α,apoptosis related proteins Bax and Bcl-2,PI3K/AKT pathway and MAPK signaling pathway.To investigate the protective effect of selenium-rich yeast combined with vitamin E on doxorubicin-induced heart injury in mice.Results: 1.General situation of miceDuring the experiment and after the experiment,the general condition of the mice was observed and analyzed.It was found that the mice in the blank group were generally in good condition,with shiny hair,good spirit,full activity,normal eating and drinking water,and a slight decrease in body weight.The mice in DOX group had reduced food intake and water intake,decreased body weight,decreased activity,and hair loss.The mice in DOX+Se Y group,DOX+Se Y+VE group and DOX+Se group had improved compared with the MICE in DOX group,with no significant difference.2.Pathological observation results of myocardial tissue in miceHE results showed that the myocardial fibers of mice in the blank group were neatly arranged and closely connected without any abnormal changes.It could be seen that the myocardial cells had a clear and complete structure with uniform nuclear size and blue-purple color without obvious structural changes.The intercellular stroma was normal without edema.Compared with Con group,myocardial cells in DOX group showed degeneration and edema,uneven nuclear size and distribution,loose and disorderly arrangement of myocardial fibers,and even fracture,and the space between myocardial interstitium was enlarged and infiltrated by inflammatory cells.This reflects the toxic effect of adriamycin on the heart.Compared with the DOX group,the inflammatory infiltration of myocardial interstitium was reduced in the DOX+Se Y group,DOX+Se Y+VE and DOX+Se groups,and the nuclear situation was improved,suggesting that the myocardial damage caused by se-enriched doxorubicin has a protective effect.3.Determination of antioxidant levels in mouse myocardium(SOD,GSH-Px)Compared with Con group,the protein contents of SOD and GSH-Px in cardiac muscle of DOX group were significantly decreased(P<0.05 or P<0.01).After treatment,SOD protein content in each group increased,and the difference was statistically significant compared with DOX group(P<0.05).The SOD protein content in DOX+Se Y+VE group was significantly higher than that in DOX group(P<0.05).4.Determination of inflammatory factors in mouse myocardium(NF‐κB,TNF‐α)The expression levels of NF‐κB and TNF‐α in DOX group were significantly increased compared with Con group(P<0.05 or P<0.01).Compared with DOX group,NF‐κB and TNF‐α protein contents in all groups were significantly decreased(P<0.05).The expression levels of NF‐κB and TNF‐α in DOX+Se Y+VE group were significantly decreased compared with DOX group(P<0.05).5.Detection of apoptosis factors in mouse myocardium(Bax,Bcl-2)Compared with Con group,Bax protein content and Bax/Bcl-2 ratio in DOX group were significantly increased,while bcl-2 protein content was decreased,and the differences were statistically significant(P<0.05).Compared with DOX group,Bax protein expression level and Bax/Bcl-2 ratio in DOX+Se Y group and DOX+Se group were decreased(P<0.05),while bcl-2 protein content was significantly increased,with statistical significance(P<0.05).At the same time,the Bax protein expression level and the Bax/Bcl-2 ratio in DOX+Se Y+VE group were significantly lower than those in DOX group(P<0.05),and the bcl-2 protein content was significantly increased(P<0.05),and the change levels were better than those in DOX+Se Y and DOX+Se groups.6.Changes of PI3K/AKT pathway in mouse myocardial tissueCompared with Con group,cardiac PI3 K protein content and P-AKT1/AKT1 ratio in DOX group were significantly decreased,with statistical significance(P<0.05 or P<0.01).After treatment,the content of PI3 K protein and p-AKT1 /AKT1 ratio were increased in all groups(P<0.05).Compared with DOX group,PI3 K protein content and P-AKT1/AKT1 ratio were significantly increased in DOX+Se Y+VE group(P<0.05),and the results were better than DOX+Se Y group and DOX+Se group.7.Changes of MAPK signaling pathway in mouse myocardiumCompared with Con group,the expression levels of phosphorylated JNK and MAPK in DOX group were significantly increased(P <0.05).After treatment,the phosphorylated JNK and MAPK protein contents in each group decreased,which was statistically significant compared with DOX group.The phosphorylated JNK and MAPK protein contents in DOX+Se Y+VE group were slightly lower than those in DOX+Se Y and DOX+Se groups,and the effect was better.Conclusion: 1.Adriamycin can cause cardiotoxicity in mice,and its mechanism may be related to oxidative stress,apoptosis,inflammatory response,PI3K-Akt signaling pathway and mitogen-activated protein kinase(MAPK)signaling pathway.2.Intragastric administration of se-enriched yeast can improve the myocardial injury and pathological changes induced by adriamycin,and has protective effect on the myocardium of mice.3.Intragastric administration of se-enriched yeast can inhibit oxidative stress,inflammatory response and apoptosis of mouse cardiomyocytes induced by adriamycin,thus reducing the damage of adriamycin to myocardium,which is related to the activation of PI3K-Akt signaling pathway.