OBJECTIVETo explore whether there is difference in arsenicals-induced DNA damage of human lymphocyte.

METHODSLymphocyte were sterilely collected from healthy donor and exposed to sodium arsenite (AsIII), sodium arsenate(AsV) and methyl sodium arsenate(MAsv) at 1,5,10,20 and 50 mumol/L. After incubation of 24 hours, cells were collected by centrifugation and DNA damage was detected by single cell gel electrophoresis (SCGE).

RESULTSThe comet frequency distribution of all groups except 1 mumol/L group of MAsV were significantly different from that of control. The comet length of all groups except 1 mumol/L group of AsV and 1.5 mumol/L groups of MAsV were significantly higher than that of control. There were correlations between the doses of arsenicals and the ratios of comet cell or length of comet(rAsIII = 0.8134, rAsV = 0.8734, rMAsV = 0.8994).

CONCLUSIONDNA damage in human lymphocyte were induced by all the three arsenicals. A dose-effect relationship was observed between exposure doses of the same arsenical and DNA damage. With different arsenicals but the same exposure dose, the DNA damage level was as follow: AsIII > AsV > MAsV.

Arsenates ; toxicity ; Arsenites ; toxicity ; Comet Assay ; DNA Damage ; Dose-Response Relationship, Drug ; Humans ; Lymphocytes ; drug effects ; ultrastructure

OBJECTIVETo study mechanism of the apoptosis of rat pancreas islet β cell strain (INS-1 cells) induced by sodium arsenite.

METHODSINS-1 cells were exposed to sodium arsenite at the different concentrations. MTT assay was used to detect the viability of INS-1 cells. The potentials on mitochondrial membrane and lysosome membrane of INS-1 cells were determined with the fluorescence spectrophotometer. The apoptotic levels of INS-1 cells exposed to sodium arsenite were observed by a fluorescence microscope and flow cytometry.

RESULTSAfter exposure to sodium arsenite, the viability of INS-1 cells significantly decreased with the doses of sodium arsenite. At 24 h after exposure, the OD values of the mitochondrial membrane potentials declined observably with the doses of sodium arsenite (P < 0.01). At 48 h after exposure, the OD values of the lysosome membrane potentials significantly increased with the doses of sodium arsenite (P < 0.01). At 72 h after exposure, the apoptotic cells were observed under a fluorescence microscope and enhanced with the doses of sodium arsenite. The apoptosis cells with light blue, karyopyknosis, karyorrhexis, apoptotic body and chromatin concentration appeared. The results detected with flow cytometry indicated that after exposure, the apoptotic INS-1E cells significantly increased with the doses of sodium arsenite.

CONCLUSIONSThe sodium arsenite can induce the apoptosis of INS-1 cells through the mitochondria-lysosome pathway.

Animals ; Apoptosis ; drug effects ; Arsenites ; toxicity ; Cells, Cultured ; Insulin-Secreting Cells ; drug effects ; Lysosomes ; metabolism ; Membrane Potentials ; drug effects ; Mitochondria ; metabolism ; Rats ; Sodium Compounds ; toxicity

Arsenites ; toxicity ; Cell Cycle ; drug effects ; Cell Division ; drug effects ; Cell Proliferation ; drug effects ; Cells, Cultured ; Dose-Response Relationship, Drug ; Humans ; Keratinocytes ; cytology ; Skin ; cytology ; Sodium Compounds ; toxicity

OBJECTIVETo investigate the relationship between the hormesis of proliferation and oxidative stress induced by sodium arsenite (Na(2)AsO(2)) in human embryo lung fibroblasts (HELF).

METHODSHELF were treated with Na(2)AsO(2) of 0.0, 0.1, 0.5, 1.0, 5.0 and 10.0 micromol/L for 4 hours or 24 hours, respectively. The cell proliferation, the reactive oxygen species (ROS) level, the malondialdehyde (MDA) content and the activity of glutathione peroxide (GSH-Px) and the superoxide dismutase (SOD) in HELF were detected respectively.

RESULTSThe HELF proliferation induced by 0.1 and 0.5 micromol/L Na(2)AsO(2) was significantly higher than that in the control group (P < 0.01). The HELF proliferation induced by 5.0 and 10.0 micromol/L Na(2)AsO(2) was significantly lower than that in the control group (P < 0.01) with the dose-effect relation of an inverted U curve. The ROS level induced by Na(2)AsO(2) of between 0.5 and 10.0 micromol/L was significantly increased (P < 0.05, P < 0.01). The positive correlation was found between the ROS level and the exposure dose of Na(2)AsO(2) (r = 0.934, P < 0.01). The 5.0 and 10.0 micromol/L Na(2)AsO(2) induced the significant increase of the MDA contents (P < 0.01) and the significant decrease of the GSH-Px activity compared to those in the control group (P < 0.01). The SOD activity in 0.5 micromol/L Na(2)AsO(2) group was significantly higher than that in the control group (P < 0.01) while the SOD activity induced by 5.0 and 10.0 micromol/L Na(2)AsO(2) was significantly decreased (P < 0.01) if compared with the control group with the dose-effect relation of an inverted U curve.

CONCLUSIONThe sodium arsenite can induce the hormesis of proliferation in HELF with the dose-effect relation of an inverted U curve. The mechanisms probably relates to different levels of oxidative stress induced by sodium arsenite of different concentrations.

Arsenites ; toxicity ; Cell Proliferation ; drug effects ; Cells, Cultured ; Dose-Response Relationship, Drug ; Fibroblasts ; cytology ; drug effects ; metabolism ; Glutathione Peroxidase ; metabolism ; Humans ; Lung ; cytology ; embryology ; Malondialdehyde ; metabolism ; Oxidative Stress ; drug effects ; Reactive Oxygen Species ; metabolism ; Sodium Compounds ; toxicity ; Superoxide Dismutase ; metabolism

OBJECTIVETo evaluate the effects of sodium arsenite on the activity, the mRNA and the protein expression of CAT in human keratinocyte cell line (HaCaT).

METHODSThe activity of catalase (CAT) was detected by ultraviolet direct velocity assay. RT-PCR was used to detect the mRNA expression of CAT and Western blotting was conducted to detect the protein expression of CAT.

RESULTSIf the cells were treated with higher than 5.0 micromol/L sodium arsenite, the activity, mRNA and protein expression of CAT were decreased significantly and in a dosage dependent fashion (P < 0.05).

CONCLUSIONCAT is inhibited by sodium arsenite in the transcription, translation and activity levels.

Arsenites ; toxicity ; Blotting, Western ; Catalase ; biosynthesis ; genetics ; Cell Line ; Dose-Response Relationship, Drug ; Humans ; Keratinocytes ; drug effects ; enzymology ; RNA, Messenger ; genetics ; Reverse Transcriptase Polymerase Chain Reaction ; Sodium Compounds ; toxicity

OBJECTIVETo observe the chronic combined effects of sodium fluoride and sodium arsenite on the Runx2 and downstream related factors of bone metabolism in SD rats.

METHODSSD rats were divided randomly into nine groups of 6 each by factorial experimental design (half female and half male) , and supplied with the different doses of fluoride, arsenite and fluoride plus arsenite containing in deionized water (untreated control containing 0 mg/kg fluoride and 0 mg/kg arsenite, and low-fluoride and high supplemented with 5 and 20 mg/kg fluoride, and low-arsenite and high supplemented with 2.5 and 10 mg/kg arsenite, and low-fluoride plus low-arsenite, and low-fluoride plus high-arsenite, and high-fluoride plus low-arsenite, and high-fluoride plus high-arsenite, respectively) . After 6 months exposure, the concentration of Runx2, matrix metallopeptidase 9 (MMP-9) ,Osterix, Receptor activator for nuclear factor-κ β ligand (RANKL) were detected by enzyme-linked immunosorbent assay method, respectively.

RESULTSThere were no dental fluorosis found in the control group, low-arsenic group and high-arsenic group. There were significant differences in the constituent ratio of dental fluorosis among the rats from low-fluoride and high-fluoride (that is 5 rats out of 6 and 6 rats out of 6) compared with the control group (0 rat out of 6) (χ(2) = 8.57, 12.00, P < 0.05). The bone fluorine level increased with the increase of fluoride dose, the groups without fluoride supply (control group, low-arsenite and high-arsenite group's geometric mean (minimum-maximum) were 0.005 (0.003-0.009), 0.006 (0.003-0.021), 0.003 (0.002-0.100) mg/g, respectively), low-fluorine groups (low-fluoride group, low-fluoride plus low-arsenite, and low-fluoride plus high-arsenite group were 3.395 (2.416-5.871), 3.809 (1.471-7.799), 1.471 (1.473-6.732)mg/g, respectively) , the high-fluorine groups (high-fluoride, high-fluoride plus low-arsenite, and high-fluoride plus high-arsenite group were 70.086 (46.183-131.927), 69.925 (40.503-96.183), 40.503 (52.622-89.487) mg/g, respectively) and the differences between groups was significant (P < 0.05). The bone arsenic level increased with the increase of arsenite dose. The low-arsenic groups (low-arsenite group, low-arsenite plus low-fluoride, and low-arsenite plus high-fluoride group were 7.195 (5.060-9.860), 6.518 (2.960-12.130), 6.970 (3.400-9.730) µg/g, respectively), the high-arsenic groups (high-arsenite, high-arsenite plus low-fluoride, and high-fluoride plus high-arsenite group's geometric mean(minimum-maximum) were 8.823 (5.760-10.840), 9.470 (7.230-12.860), 8.321 (2.420-17.540) µg/g, respectively) were significantly higher than that in the groups without arsenic supply (control group, low-fluoride and high-fluoride group were 1.785 (0.300-3.750), 2.226 (1.410-3.980), 2.030 (1.040-3.850)µg/g, respectively) (P < 0.05). There was no significant difference of the bone arsenic concentration between low-arsenic and high arsenic group. There was significant positive correlation between fluoride concentration and Runx2, MMP-9, Osterix, RANKL level (the correlation coefficient was 0.647, 0.354, 0.582, 0.613 between fluorine gavage concentration and protein level, the correlation coefficient was 0.559,0.387, 0.487, 0.525 between bone fluorine concentration and protein level, respectively, P < 0.01). There was negative correlation between arsenite gavage concentration with Runx2 level (r = -0.527, P < 0.05) and was no correlation between arsenite gavage concentration with MMP-9, RANKL,Osterix level (P > 0.05). There was interaction between fluoride and arsenite to Runx2, MMP-9, RANKL,Osterix (F = 3.88, 15.66, 2.92, 6.42, respectively, P = 0.01, <0.01, 0.031, <0.01, respectively).

CONCLUSIONThe combined effects of fluoride and arsenic on the Runx2, MMP-9, RANKL, Osterix of bone metabolism showed antagonistic effects.

Animals ; Arsenites ; toxicity ; Bone and Bones ; metabolism ; Core Binding Factor Alpha 1 Subunit ; metabolism ; Environmental Exposure ; Female ; Fluorides ; toxicity ; Fluorosis, Dental ; pathology ; Male ; Matrix Metalloproteinase 9 ; metabolism ; RANK Ligand ; metabolism ; Rats ; Rats, Sprague-Dawley ; Transcription Factors ; metabolism

BACKGROUND: Arsenic is a developmental neurotoxicant. It means that its neurotoxic effect could occur in offspring by maternal arsenic exposure. Our previous study showed that developmental arsenic exposure impaired social behavior and serotonergic system in C3H adult male mice. These effects might affect the next generation with no direct exposure to arsenic. This study aimed to detect the social behavior and related gene expression changes in F2 male mice born to gestationally arsenite-exposed F1 mice. METHODS: Pregnant C3H/HeN mice (F0) were given free access to tap water (control mice) or tap water containing 85 ppm sodium arsenite from days 8 to 18 of gestation. Arsenite was not given to F1 or F2 mice. The F2 mice were generated by mating among control F1 males and females, and arsenite-F1 males and females at the age of 10 weeks. At 41 weeks and 74 weeks of age respectively, F2 males were used for the assessment of social behavior by a three-chamber social behavior apparatus. Histological features of the prefrontal cortex were studied by ordinary light microscope. Social behavior-related gene expressions were determined in the prefrontal cortex by real time RT-PCR method. RESULTS: The arsenite-F2 male mice showed significantly poor sociability and social novelty preference in both 41-week-old group and 74-week-old group. There was no significant histological difference between the control mice and the arsenite-F2 mice. Regarding gene expression, serotonin receptor 5B (5-HT 5B) mRNA expression was significantly decreased (p < 0.05) in the arsenite-F2 male mice compared to the control F2 male mice in both groups. Brain-derived neurotrophic factor (BDNF) and dopamine receptor D1a (Drd1a) gene expressions were significantly decreased (p < 0.05) only in the arsenite-F2 male mice of the 74-week-old group. Heme oxygenase-1 (HO-1) gene expression was significantly increased (p < 0.001) in the arsenite-F2 male mice of both groups, but plasma 8-hydroxy-2'-deoxyguanosine (8-OHdG) and cyclooxygenase-2 (COX-2) gene expression were not significantly different. Interleukin-1β (IL-1β) mRNA expression was significantly increased only in 41-week-old arsenite-F2 mice. CONCLUSIONS These findings suggest that maternal arsenic exposure affects social behavior in F2 male mice via serotonergic system in the prefrontal cortex. In this study, COX-2 were not increased although oxidative stress marker (HO-1) was increased significantly in arsnite-F2 male mice.
Animals ; Arsenic/toxicity* ; Arsenites/toxicity* ; Behavior, Animal/drug effects* ; Environmental Pollutants/toxicity* ; Female ; Gene Expression/drug effects* ; Genetic Markers ; Male ; Maternal Exposure/adverse effects* ; Mice ; Mice, Inbred C3H ; Oxidative Stress/genetics* ; Prefrontal Cortex/drug effects* ; Pregnancy ; Prenatal Exposure Delayed Effects/psychology* ; Reverse Transcriptase Polymerase Chain Reaction ; Serotonin/metabolism* ; Social Behavior ; Sodium Compounds/toxicity*

BACKGROUNDExcessive reactive oxygen species (ROS) may lead to a number of reproductive diseases such as polycystic ovary syndrome. This study aimed to establish an animal model of ovarian oxidative stress and to assess the protective effect of curcumin against oxidative injury.

METHODSOvarian oxidative stress was induced in female Kunming mice (n = 40) with intraperitoneal injection of 8 mg/kg sodium arsenite (As) once every other day for 16 days; meanwhile, they were, respectively, treated by intragastric administration of 0, 100, 150, or 200 mg/kg (n = 10/group) curcumin once per day for 21 days. Ten normal mice were used as control. Then, the mice were injected intraperitoneally with BrdU and sacrificed; the right ovaries were collected for hematoxylin and eosin (HE) staining and BrdU immunohistochemistry, and the left ovaries for enzyme-linked immunosorbent assay (ELISA) and Western blotting analyses.

RESULTSThe ELISA results showed that ROS (11.74 ± 0.65 IU/mg in 8 mg/kg AS + 0 mg/kg curcumin group vs. 10.71 ± 0.91 IU/mg in control group, P= 0.021) and malondialdehyde (MDA) (0.32 ± 0.02 nmol/g in 8 mg/kg AS + 0 mg/kg curcumin group vs. 0.27 ± 0.02 nmol/g in control group, P= 0.048) increased while superoxide dismutase (SOD) (3.96 ± 0.36 U/mg in 8 mg/kg AS + 0 mg/kg curcumin group vs. 4.51 ± 0.70 U/mg in control group, P= 0.012) and glutathione peroxidase (17.36 ± 1.63 U/g in 8 mg/kg AS + 0 mg/kg curcumin group vs. 18.92 ± 1.80 U/g in control group, P= 0.045) decreased in the ovary after injection of As, indicating successful modeling of oxidative stress. Curcumin treatment could considerably increase SOD (4.57 ± 0.68, 4.49 ± 0.27, and 4.56 ± 0.25 U/mg in 100 mg/kg, 150 mg/kg, and 200 mg/kg curcumin group, respectively, allP < 0.05) while significantly reduce ROS (10.64 ± 1.38, 10.73 ± 0.71, and 10.67 ± 1.38 IU/mg in 100 mg/kg, 150 mg/kg, and 200 mg/kg curcumin group, respectively, allP < 0.05) and MDA (0.28 ± 0.02, 0.25 ± 0.03, and 0.27 ± 0.04 nmol/g in 100 mg/kg, 150 mg/kg, and 200 mg/kg curcumin group, respectively; bothP < 0.05) in the ovary. HE staining and BrdU immunohistochemistry of the ovarian tissues indicated the increased amount of atretic follicles (5.67 ± 0.81, 5.84 ± 0.98, and 5.72 ± 0.84 in 100 mg/kg, 150 mg/kg, and 200 mg/kg curcumin group, respectively, all P < 0.05), and the inhibited proliferation of granular cells under oxidative stress would be reversed by curcumin. Furthermore, the Western blotting of ovarian tissues showed that the p66Shc expression upregulated under oxidative stress would be lowered by curcumin.

CONCLUSIONCurcumin could alleviate arsenic-induced ovarian oxidative injury to a certain extent.

Animals ; Arsenites ; toxicity ; Curcumin ; therapeutic use ; Disease Models, Animal ; Enzyme-Linked Immunosorbent Assay ; Female ; Glutathione Peroxidase ; metabolism ; Immunohistochemistry ; Malondialdehyde ; metabolism ; Mice ; Ovary ; drug effects ; metabolism ; Oxidative Stress ; drug effects ; Polycystic Ovary Syndrome ; drug therapy ; metabolism ; Reactive Oxygen Species ; metabolism ; Sodium Compounds ; toxicity ; Superoxide Dismutase ; metabolism