Deoxynivalenol (DON) and Aflatoxin B1 are the most prevalent mycotoxins in cereal-based ingredients or foods and they fiequently coexist.HepG2/C3A cell treated with different concentrations of DON(0.56、1.125、2.25、4,5、6.75 μ mol/L) and AFB1 (2.5、5、10、20、30 μmol/L)for 24 h was used to analyze their toxic effects expressed by cell proliferation inhibition rate (SRB),total double-stranded DNA,apoptosis rate,cell cycle arrest and apoptosis-related gene,caspase-3,Bax,Bcl-2 were analyzed by real-time quantitative PCR.The results showed that their co-effect was classified as being additive.Flow cytometry assay on the rate of apoptosis also shown an additive interaction which could indicated that these two toxins could induced apoptosis and they also induced cycle arrest in S-phase or S,G2/M-phase.The increase of expression ofcaspase-3 and Bax as well as the decrease of Bcl-2 further support their additive toxic effect.RNA-Seq analysis showed different cytotoxicity mechanism between AFB1 and DON that AFB1 and their combination effect induce cell apoptosis mainly through P53 pathway while not for DON.We guess AFB1 and DON may through different pathway to induce cell apoptosis together.%脱氧雪腐镰刀菌烯醇(DON)和黄曲霉毒素B1(AFB1)是一类常见的毒素类污染物,常共存于小麦、玉米等食品及制品中.实验采用不同浓度的DON(0.56、1.125、2.25、4.5、6.75 μmol/L)和AFB1(2.5、5、10、20、30μmol/L)单独及联合作用于HepG2/C3A细胞24 h后,分别测定细胞增殖抑制率(SRB)、双链DNA含量变化以及低浓度条件下细胞凋亡率和细胞周期分布,采用RTq-PCR测定凋亡相关基因caspase-3、Bax以及Bcl-2 mRNA的相对含量.最后通过RNA-Seq测序分析2种毒素作用的毒性机理.结果显示,2种毒素单独及混合作用于HepG2/C3A细胞后使得细胞增殖抑制率增加,双链DNA含量下降,经分析后发现两者联合作用类型为加和作用.低浓度作用下均能引起细胞发生凋亡,使得细胞阻滞在S期或者S期和G2/M期,并且引起caspase-3和Bax表达量增加,Bcl-2则下降,从而引发细胞凋亡.RNA-Seq测序结果显示,经过差异基因的富集分析,AFB1与DON的毒性作用机理并不相同,其中AFB1以及两者的混合作用主要是通过P53信号通路影响细胞凋亡,而DON并不是.AFB1与DON可能是通过2种不同的途径一起共同导致细胞凋亡的发生.
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