The Analysis Of MiRNA Expression Profiles In The Exosomes Of SMB-S15 Treated With Resveratrol

Prion diseases(PrPs),also designated as transmissible spongiform encephalopathies(TSEs),are a group of fatal(fatal rate 100%)neurodegenerative disorders that affect both humans and many other mammalian animals.A possible pathogenesis of TSEs is a transformation of normal prion protein(PrPC)into an abnormal form(PrPSc)which is infectious.Exosomes are small 50-130 nm vesicles released from cells and play an important role in the spread of prions.Exosomes also contain microRNAs(miRNAs),a class of non-coding RNA,and consists of 18-24 ribonucleotides.Research shows some miRNAs abnormal expression in prion-infected brain tissue.miRNA is selectively incorporated into exosomes as opposed to random events or contamination during the process of exosome isolation.It is proved that miRNA in exosomes plays an important role in the development of disease.Resveratrol is a natural polyphenolic phytoalexin that is synthesized in response to stress in a number of fruits and vegetables.Our previous study has proposed that the natural phytoalexin,resveratrol,can reduce the amounts of PrPSc in a scrapie-infected cell line SMB-S15.However,the mechanism is not clear.To investigate the changes of miRNAs in extracellular exosomes during resveratrol clearance of PrPSc from SMB-S15 cells,we extracted exosomes miRNA from prion-infected cells SMB-S15(S15),exposure of SMB-S15 to resveratrol for 4 days(RES4),exposure of SMB-S15 to resveratrol for 8 days(RES8),and PrPSc removed SMB-S15 cells(PS),and miRNAs Deep sequencing was performed to analyze the differential expression of miRNAs in 4 groups.Then analyze the signaling pathways involved in differentially expressed miRNAs through GO and KEGG pathwayConsistent with the results of previous laboratory experiments,it was found that the content of PrPSc in the cells decreased significantly when resveratrol was used to treat SMB-S15 cells for 4 days,and PrPSc in the cells could not be observed at all after 8 days of treatment.In order to explore whether there is a regular pattern of miRNA expression during the clearance of PrPSc in cells,We examined the miRNAs in exosomes that were infected with prions after 4 and 8 days of resveratrol treatment.The results showed that the differences in expression were very significant and complex.Using the S15 group as a control,we found that the RES8 group was up-regulated or down-regulated by more than 8 times the miRNAs and found that:22miRNAs showed an increasing trend in the three groups of S15,RES4 and RES8;52 miRNAs showed a trend of decreasing first and then increasing;6 miRNAs showed a trend of increasing first and then decreasing;4 miRNAs showed a gradual decrease.The PS cells are the cells of S15 cells that have been cleared of PrPSc by pentosulfate.The S15 group was used as a control.We compared the different changes of miRNA in RES8 and PS groups those PrPSc were cleared with different drugs.The results showed that the majorty of miRNAs in the two exosomes were all up-expressed.they accounted for 62.1%and 82%of the total miRNA changes,respectively.Analysis of both KEGG and Go revealed involvement of similar cellular physiological functions.At the same time,we compared the changes of miRNAs in the RES8 and PS group with the S15 group as a control:we found that the differences in the expression of miRNAs in exosomes after resveratrol and pentosan sulfate removal were similar,and there were 10 species miRNAs were upregulated by more than 8 fold in both groups,and 7 miRNAs were down-regulated by more than 8 fold in both groups.Exosomes are important media for exchanging information between cells,and they are also important ways for viruses to spread between cells.Changes in the composition of exosomes are closely related to the occurrence and development of the disease.In this study,we examined the expression changes of miRNAs in exosome of prion-infected cells which were treated with resveratrol.Provides important scientific data for understanding the mechanisms of prion disease and transmission.At the same time,exosomes are easily accessible and non-invasive biological samples.At the same time,exosomes are easily obtained biological samples without damage to the human body,the search for disease-associated miRNAs in exosomes also aids in the diagnosis of the disease.