The Study Of DNA Damage In INS-1 Cell And Its Mechanisms Induced By Acrylamide

Objects: 2015 report on Chinese resident’s chronic disease and nutrition showed that the diabetes prevalence was 9.7% in Chinese adult population above 18 years old in 2012.Based on the data from International Diabetes Federation,there are about 4.15 hundred million diabetes patients,which accounts for 8.8% of adult between 20 and 79 years old around the world.The evidence have indicated that exposure to environmental chemicals could cause the damage of pancreatic β cell and inhibit the synthesis and secretion of insulin,which finally induced diabetes.Acrylamide(AA)is a type of chemical material to synthesis polyacrylamide,widely used in adhesive,textilemanufacturing,stabilizer in cement production and scientific research and so on.Occupational exposure to acrylamide are mainly through skin,dust and inhalation,while general population may exposure to acrylamide by the intake of the polluted food and water or by smoking.Studies have suggested the toxicity of acrylamide on nerve,reproduction and heredity,and it has been identified as a carcinogen in the list of International Agency for Research on Cancer group 2A.However,the evidence of acrylamide on the damage of islet cells was limit.In order to investigate of the effects of acrylamide on INS-1 cell,we detected the cell viability,the indexes of DNA damage and oxidative stress.The results would be helpful to evaluate the harmful impact of acrylamide on multiple organs.Methods: INS-1 cell treated with 0mmol/L(blank control)、2mmol/L、4mmol/L and 8mmol/L acrylamide.Cell toxicity was detected using MTT method.Single cell gel electrophoresis(SCGE)was used to detect the DNA damage.And we measured the reactive oxygen species(ROS),the stability of lysosomal membrane and the mitochondrial membrane potential(MMP)with 2’,7’-dichlorofluorescein,acridine orange and Rhodamine 123,respectively.Moreover,we treated the cells with N-acetyl-L-cysteine(NAC)to detected its anti-oxidative damage effects and discuss the toxic mechanisms induced by acrylamide.Statistical analysis was performed using SPSS 18.0.Comparisons were made by one-way ANOVA followed by Fisher’s least significant difference(LSD)post hoc analysis with P < 0.05 considered statistically significant.Results:(1)MTT results showed that cell viability of all AA treated cells was significantly lower than control(P<0.05),and the absorbance decreased with the treatment dosage.(2)SCGE results showed the significant differences in tail length,tail moment and tail DNA% among four AA treatment groups(P < 0.05),and they exhibited the line a dose-response relationships.(3)The oxidative damage results showed that in 4mmol/L and 8mmol/L group of AA treatment,the ROS content increased,the stability of lysosomal membrane decreased,the mitochondrial membrane potential decreased,and all above significantly different from control(P < 0.05).(4)After pretreatment of NAC in 8mmol/L group,the indexes of oxidative damage were affected by AA compared with control(P < 0.05),NAC may have a protective effect on oxidative damage induced by AA.Conclusions:(1)Acrylamide showed the genotoxicity on INS-1 cell.(2)Acrylamide may induce DNA damage through oxidative stress pathway.(3)DNA damage caused by acrylamide may be related to the damage of lysosome and mitochondria.(4)NAC could protect DNA damage of INS-1 from acrylamide treatment.