title: [A study on apoptosis and apoptotic mechanisms of HL-7702 cell line induced by methylmercury].
abstract: OBJECTIVE
  To study the apoptotic effect and mechanisms of methylmercury (MeHg) on HL-7702 cell line in vitro.
  
  
  METHODS
  In this study, the cell apoptosis was observed by AO/EB method and FCM method; the mitochondrial membrane potential was detected by FCM; and the expression of proteins related to apoptosis was measured by immunocytochemical method.
  
  
  RESULTS
  After exposure to MeHg for 24 h in different doses, apoptotic rate ascended with the increasing of MeHg concentration. By AO/EB method, cell apoptotic ratio of negative control group was (2.62 +/- 0.19)%, cell apoptotic ratio of 10-50 micromol/L exposure groups were (7.97 +/- 0.64)%, (12.66 +/- 0.76)%, (19.16 +/- 0.87)%, (18.42 +/- 0.88)%, and (11.52 +/- 0.63)%, there were significant differences between the exposure and negative control groups (q values were 17.057, 32.009, 52.732, 50.373, 28.375; P<0.05). Mitochondrial membrane potential descended with the increase of MeHg, mitochondrial membrane potential of negative control group was (10.23 +/- 3.43) mV, mitochondrial membrane potential of 10-50 micromol/L exposure groups were (3.25 +/- 0.66), (3.03 +/- 0.35), (1.68 +/- 1.26), (1.69 +/- 1.13) and (1.77 +/- 0.88) mV, and there was significant differences between exposure and negative control groups (q values were 9.569, 9.871, 11.722, 11.708, 11.598; P<0.05). The expression of Bax, Bcl-2, CytC, Caspase-3 and AIF enhanced with the increase of MeHg, Bax/Bcl-2 ratio also appeared a trend of increase. Bax expression integral optical density (IOD) of negative control group was (21295.86 +/- 1969.81), Bax expression IOD of 10, 20, 30 micromol/L groups were 42807.87 +/- 4416.64, 55651.65 +/- 4662.72, and 72708.56 +/- 910.10, there were significant differences in Bax expression between 10, 20, 30 micromol/L groups and negative control group (q values were 14.191, 14.320, 33.917; P<0.05); Bcl-2 expression IOD of negative control group was (12588.33 +/- 4091.02), Bcl-2 expression IOD of 10, 20, 30 micromol/L groups were 20539.16 +/- 4906.09, 23689.97 +/- 2281.42, and 28692.80 +/- 4655.86, there were significant differences in Bcl-2 expression between 10, 20, 30 micromol/L groups and negative control group (q values were 4.322, 6.035, 8.754; P<0.05); and AIF expression IOD of negative control group was (12942.72 +/- 457.94), AIF expression IOD of 10, 20, 30, 40 micromol/L groups were 16973.57 +/- 1922.87, 29998.91 +/- 6803.58, 52467.16 +/- 1916.25 and 106342.53 +/- 1273.19, there were significant differences in AIF expression between 20, 30 and 40 micromol/L groups and negative control group (q values were 11.449, 26.530, 62.692; P<0.05).
  
  
  CONCLUSIONS
  MeHg could induce apoptosis on HL-7702 cell line in vitro. The mechanisms could be related to mitochondrial pathway in apoptosis.
authors.affiliation: School of Public Health, Jilin University, Changchun 130021, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Sun
authors.forename: Wen
authors.initials: W
authors.lastname: Wang
authors.forename: Xiao-mei
authors.initials: XM
authors.lastname: Liu
authors.forename: Ming-hua
authors.initials: MH
authors.lastname: Jin
authors.forename: Hai-ying
authors.initials: HY
authors.lastname: Du
authors.forename: Dan-bing
authors.initials: DB
authors.lastname: Peng
authors.forename: Zhi-wei
authors.initials: ZW
authors.lastname: Sun
mesh_terms: D017209:Apoptosis / Q000187:drug effects*; D002460:Cell Line; D005434:Flow Cytometry; D022781:Hepatocytes / Q000166:cytology / Q000187:drug effects; D006801:Humans; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects*; D008767:Methylmercury Compounds / Q000494:pharmacology*; D024101:Mitochondrial Proteins / Q000378:metabolism
chemical_list: D008767:Methylmercury Compounds; D024101:Mitochondrial Proteins