Differential Expression Of Small Heat Shock Proteins HSP20,HSP22 And HSP27 In Stable And Unstable Carotid Plaques

Objective: Stroke is a kind of disease with high disability and death rate that seriously endangers human health,and it brings huge economic burden to families and countries.The formation of carotid atherosclerotic plaque is closely related to ischemic stroke and is one of the main causes of ischemic stroke.According to the findings of carotid endarterectomy combined with Stary classification,we divided carotid plaques into stable plaques and unstable plaques.The unstable plaque rupture or thrombosis of carotid atherosclerosis can cause the occurrence of stroke.In most patients with carotid stenosis,the whole pathological process seems to be silent clinically.Most work in the field of plaque imaging is usually done after symptom events.Although the explosive development of imaging data analysis may greatly help accelerate its implementation,it is still too early to determine whether these technologies can be used in clinical practice in the near future.Therefore,it is necessary for us to start looking for biological markers related to plaque stability.Under pathological conditions,specific heat shock proteins show different functions and are closely related to atherosclerosis.In the pathogenesis of carotid atherosclerosis,it can play a protective role(HSP27)and also play an atherogenic role(HSP70).HSP20 can play an anti-atherosclerosis role.The anti-atherosclerosis effect of HSP20 may be exerted through platelet pathway.HSP22 is a small molecular weight protein preferentially expressed in the heart.In human and animal models after acute and chronic ischemia,the expression of HSP22 increased significantly under the condition of cardiac oxidative stress.The plasma level of HSP27 in patients with acute coronary syndrome is lower than that in healthy controls,as is the case in patients with carotid stenosis.The above related studies have brought HSP20,HSP22 and HSP27 into our field of vision.The purpose of this paper is to discuss whether there is differential expression of HSP20,HSP22 and HSP27 in stable and unstable carotid plaques and the correlation between differential expression and plaque stability.The aim is to find markers to track the progression of atherosclerosis,detect so-called "vulnerable patients" and predict rupture events in time to avoid the arrival of fatal end points.And to explore the possible mechanism of the differential expression of HSP20,HSP22 and HSP27 in stable and unstable carotid plaques.Methods: From January 1,2015 to October 1,2018,we selected 51 patients with carotid stenosis diagnosed by neurosurgery in Shengjing Hospital affiliated to China Medical University and underwent surgical stripping.According to the findings of carotid endarterectomy combined with Stary classification,we divided carotid plaques into stable plaques and unstable plaques.Stable plaques are defined as plaques with thick fibers or fibrous calcifications,lined with endothelium and covered with central foam or necrotic core(stable plaques conform to Stary’s classification types Ⅳ,ⅤB and ⅤC).Unstable plaque is defined as plaque with thin fibrous cap or fissure cap covering foam or necrotic core,which shows hemorrhagic,ulcerative or thrombotic plaque(unstable plaque conforms to Stary’s classification type VI).The clinical general conditions of all51 patients in the experimental group,including gender,age,history of hypertension,history of diabetes,coronary artery disease,homocysteine,high-sensitivity C-reactive protein,total cholesterol,triglyceride,high-density lipoprotein cholesterol and low-density lipoprotein cholesterol,were collected for statistical analysis,and the relationship between the above clinical conditions and plaque stability was analyzed.The imaging data and clinical pathological diagnosis reports of 16 patients in 51 patients were taken to analyze the differences of imaging manifestations and pathology between patients with stable carotid plaque and patients with unstable carotid plaque.These 16 patients included 8 patients with unstable carotid plaque and 8 patients with stable carotid plaque.Among 51 patients,26 patients kept serum before operation and the corresponding carotid plaque tissue during operation.Of these 26 plaques,13 were unstable plaques,and 13 sera corresponding to these 13 unstable plaques were used as the experimental group.Among these 26 cases,13 cases were stable plaques,and 13 cases of stable plaques and their corresponding 13 serum were used as control group.The levels ofgladexpression with HSP20,HSP22 and HSP27 in stable and unstable carotid plaques were detected by WESTERN BLOT.The expression levels of HSP20 mRNA,HSP22 mRNA and HSP27 mRNA in stable and unstable carotid plaques were detected by RT-qPCR.The expression,levels,,of HSP20,HSP22,and HSP27 in serum of patients with stable carotid artery stenosis and patients with unstable carotid artery stenosis were detected by ELISA.Immunohistochemical staining(IHC)was used to detect HSP20,HSP22 and HSP27 in carotid plaque tissue samples of 51 patients with carotid artery stenosis(including 23 patients with unstable carotid artery stenosis and 28 patients with stable carotid artery stenosis)to determine their expression sites and levels.And analyze the correlation between the above results and plaque stability.Results:Histological WESTERN BLOT showed that the expression levels of HSP20,HSP22 and HSP27 in stable carotid plaque were higher than those in unstable carotid plaque(P<0.01).Histological RT-qPCR results showed that the expression levels of HSP20 mRNA and HSP27 mRNA in stable carotid plaque were higher than those in unstable carotid plaque(P<0.01).There was no significant difference in the expression level of HSP22 mRNA between stable carotid plaque and unstable carotid plaque(P > 0.05).The results of serological ELISA showed thatkthekexpressionklevelskof HSP20,HSP22 and HSP27 in the serum of patients with stable stenosis were higher than those in patients with unstable stenosis(P<0.01).The results of IHC showed that the expression levels of HSP20,HSP22 and HSP27 in stable carotid plaque were higher than those in unstable carotid plaque.By analyzing the correlation of WESTERN BLOT,serological ELISA and IHC results,it was found that the high expression of HSP20,HSP22 and HSP27 in patients with stable carotid stenosis was consistent with the low expression of HSP20,HSP22 and HSP27 in patients with unstable carotid stenosis.Conclusions:1.Small heat shock proteins(HSP20,HSP22 and HSP27)have obvious differential expression in stable and unstable human carotid plaques and the same trend in serum.2.High-level expression of small heat shock proteins HSP20,HSP22 and HSP27 in the serum of patients with carotid artery stenosis predicts the stability of carotid plaques,and low-level expression in the serum of patients with carotid artery stenosis predicts the instability of carotid plaques.