Experimental Research On Differential Protein Of Myocardial Injury In Acute MDMA Exposed Rats By ITRAQ Technique

【Background】3,4-Methylenedioxymethamphetamine(MDMA)is the main component of the new type drug " Ecstasy ".After taking the drug,it can produce euphoria,ecstasy,intimacy,sociability and other mental excitement performance and slight hallucinogenic effect.In the early 1980 s,MDMA was sold publicly as a recreational drug and began to become widely popular.Following that,MDMA abuse brought serious public health and safety problems.With the increase of the number of abuse,in forensic examination and clinical work,MDMA acute poisoning and death cases are also common.A large number of previous studies have confirmed that MDMA has direct cardiotoxicity,specifically manifested as tachycardia or bradycardia,hypo/hypertension,arrhythmia,myocardial ischemia,heart failure,etc.Histopathological examination revealed myocardial necrosis hypertrophy,fibrosis,atrophy,necrosis with inflammatory infiltration,dilated cardiomyopathy,hypertrophic cardiomyopathy,etc.MDMA cardiotoxicity becomes one of the focus of forensic toxicology.However,the specific mechanism of MDMA cardiotoxicity remains limited,and whether there may be corresponding protein markers to help clinical diagnosis and treatment,as well as forensic examinations remain to be explored.【Objectives】To establish a rat model of myocardial injury caused by acute MDMA poisoning and to detect the differentially expressed proteins by i TRAQ proteomics combined with bioinformatics analysis,with a view to providing a direction for future research.To validate calcium signaling proteins and contractile proteins,in order to preliminarily explore the mechanism of acute cardiotoxicity of MDMA in rat models.【Methods】SD male rats of healthy and clean grade with a body weight of 250±20 g were randomly divided into control group,low-dose group and high-dose group.The rats in the experimental group were intraperitoneally injected with MDMA at 15.17 mg/kg and 30.34 mg/kg,respectively,and the rats in the control group were injected with the equivalent dose of normal saline.Following intraperitoneal injection of 10% chloral hydrate at a dose of 3 ml/kg,serum and heart tissue were extracted 24 h later for examination.The serum levels of c-TNT and BNP of rats were detected by enzyme-linked immunoassay.Myocardial tissue was stained with HE and histopathological examination was performed.Protein was extracted from cardiac tissue and labeled with i TRAQ.The differentially expressed proteins were detected by nano-HPLC-MS/MS.GO and KEGG pathway bioinformatics analysis were performed.Western blot was used to verify Ca MKⅡγ,NCX1 and Myh-7 proteins.【Results】1.The serum levels of c-TNT and BNP of rats exposed to MDMA were significantly higher than those in the control group(p<0.0001).There were myocardial cell necrosis with inflammatory infiltration,myocardial interstitial hemorrhage and punctate inflammatory cell infiltration in the exposed rats.2.The number of differential proteins(fold change>1.2 and p<0.05)between the highdose group and the control group,the low-dose group and the control group,the high-dose group and the low-dose group were 345,591 and 585,respectively.The main enrichment results of GO analysis were small molecule metabolism of carboxylic acid and ketone acid,redox biological process,molecular functions including protein binding such as actin,and ion binding,cellular components such as organelles represented by exosomes,cytoplasm and extracellular matrix.A total of 104 differential pathways were enriched by KEGG pathway analysis,among which 31 shared pathways were found.3.Compared with the control group,the expression of Ca MKⅡγ was increased and the expression of NCX1 and Myh-7 were decreased in the experimental group(p<0.05).【Conclusions】Acute MDMA exposure can cause myocardial tissue damage and differential protein expression in rats.Abnormal expression of Ca MKⅡγ,NCX1 and Myh-7 may be involved in MDMA acute cardiotoxicity.Oxidative stress,monoamine neurotransmitter pathways,exosome,actin binding,ion binding function,PI3K-Akt pathway,GABA neuronal synaptic pathway,energy metabolism,circadian entrainment,arrhythmogenic right ventricular cardiomyopathy,hypertrophic cardiomyopathy,dilated cardiomyopathy,etc.,may be the potential mechanism of MDMA cardiotoxicity and need to be explored in future studies.