| Di(2-ethylhexyl) phthalate(DEHP),widely used as plasticizers,has been detected in the environment and human beings.DEHP was found to exist in the air particles and showed pulmonary toxicity.Extracellular vesicles(EVs)are small lipid bilayer particles released by cells.It has many contents,including rna,proteins,lipids,and other signaling molecules,which can be transmitted between cells.One class of extracellular vesicles of small size we call small Extracellular vesicles(s EV),and we found that s EV can mediate the pulmonary toxicity of DEHP.However,little is known about the role of s EVs in mediating DEHP-induced pulmonary toxicity.We hypothesized that s EV mediated the toxicity of DEHP through their cargo.To validate this,lung epithelial cells(A549)were exposed to various concentrations(0,0.2,2 and 20 μM)of DEHP for 48 hrs.s EV extracted from DEHP-exposed A549 cells were cultured with unexposed A549 cells.Results showed that DEHP induced the epithelial-mesenchymal transition(EMT)and promoted the migration and invasion ability of A549 cells.The number of released s EV significantly increased in the culture media in DEHP-exposed groups compared to unexposed groups.The s EV can enter the unexposed A549 cells and enhance its EMT and the ability of migration and invasion ability.Treatment of DEHP exposed A549 cells with gw4869,an inhibitor of s EV secretion,almost blocked the effect of DEHP induced s EV of adjacent A549 cells.Sequencing and functional analysis showed that the enrichment of significantly differentially expressed s EVmi RNAs were related to tumor etiology.Mi R-26a-5p was significantly enriched in DEHP-elicited s EV.Inhibition of mi R-26a-5p in DEHP-exposed cells led to the downregulation of mi R-26a-5p in s EV,and thus abolished the effects of DEHP-elicited s EV in normal A549 cells,whereas overexpression of mi R-26a-5p restored the effects.The transcription factors twist is one of the downstream targets in the effects of s EV-mi R-26a-5p on EMT process.To further explore its possible mechanism of action,experiments were conducted using coincubation,and the transcription factor twist was found to be one of the downstream targets of the effect of s EV-mi R-26a-5p on the EMT process,suggesting that its action may affect its EMT process through the regulation of twist.In conclusion,our results of the present study suggest confirm that DEHP exposure promotes the secretion of mi R-26a-5p in s EV,which subsequently further enhances the EMT,migration and invasion invasion of adjacent A549 cells via twist. |
