The Research On The Suppression And Mechanism Of3-monochloro-1,2-propanediol In Food On Mice T Lymphocytes

The study is funded by Chinese Postdoctoral Science Fund Projects801120106201.Great attention has been paid to chloropropanols which have been concerned as foodcontaminants.3-monochloro-1,2-propanediol (α-chlorohydrin,3-MCPD) is the mostcommon kind of chloropropanols in behalf of the material. In the process of the productionof amino acids using the method of acid hydrolyzed vegetable protein, it inevitablyproduces chloropropanols by-products. The highest content of chloropropanol compunds is3-MCPD Compared with the traditional fermentation brewing industry, acid hydrolysisprocess has the advantages of short production periods and low cost. So the mode ofproduction has been widely used. The acid hydrolysis of protein were further processed.The pollution of3-MCPD is more common in the preparation of soy sauce and seasoning.In our study,3-MCPD(+)(purity98%) is treated as the object of the research. The weightof18-22g BALB/c mice are as the experimental animals. In the appropriate range of doses,we investigate the immunosuppressive effects of3-MCPD(+) on BALB/c mice Tlymphocytes and explore the potential action mechanism. The research conclusions are asfollows:(1) Screening the nontoxic range of doses for the research by MTT method andfurther determining the doses of3-MCPD(+). In the range of0to4mM, the absorbanceshave no significant difference compared with the blank value. It indicates that the range ofdoses is non cytotoxic for mouse spleen cells of BALB/c. Further we identified that1,2,4mM doses of3-MCPD(+) have notable inhibitory effects on T lymphocytes by treatingcells by concanavalin A stimulation.(2) We investigated the immunosuppressive effects of3-MCPD(+) on BALB/c mice Tlymphocytes by the datas and explored the possible action mechanism. Representativeimmunological tests such as flow cytometry analysis, ELISA kit, RNA isolation andsemiquantitative reverse transcription polymerase chain reaction (RT-PCR), determinationof intracellular calcium by fluorescence were ultilized in the experiment. Our datasuggested that the cell supernatant treated with1,2or4mM of3-MCPD(+) significantlydecreased compared to those of ConA group in dose-dependent manner. We analyzed theeffects of3-MCPD(+) on ConA-induced NF-B, NFAT2, AP-1signalling pathways activation by electrophoresis experiments. We found that after ConA stimulation, theexpression of NF-B, NFAT2and AP-1protein increased. But with the dose of3-MCPD(+)increased, the expression of the three protein decreased. In a dose-dependent manner,3-MCPD(+) has immunosuppressive effects on BALB/c mice spleen lymphocytes. Theinhibition effect mainly actions through NF-B, NFAT2and AP-1signal pathways.(3) Delayed type hypersensitivity reaction to dinitrofluorobenzene in mice (DTH).The analysis of the external ear tissue were made. The results showed that3-MCPD(+)also has inhibitory effects on BALB/c in vivo.In summary,3-MCPD has suppressive effects on the mice immune response and theeffects metioned was in dose-dependent manner. We hope that our research can providetoxicological basis for further safety assessment of3-MCPD in food.