The Co-induce Exposure Of Molybdenum And Cadmium On Oxidative Damage In Duck Tubular Epithelial Cells

This study was aimed to investigate the co-induced effects of Molybdenum(Mo)and Cadmium(Cd)on Oxidative Damage in Duck tubular epithelial cells.the primary cultures of duck proximal tubular cells were cultured by mechanical grinding,filtering and chemical digestive methods.(NH4)6Mo7O24·4H2O and 3CdSO4·8H2O as poison used staining for ALP(Gomori method),MTT method and chemical method respectively to identify cells,Effects of tubular epithelial cells on changes of morphological and molybdenum and cadmium exposure of IC50 at 12 h.Effects of molybdenum(480 μmol/L,960 μmol/L)and/or cadmium(2.5 μmol/L,5 μmol/L)(480μmol/LMo+2.5 μmol/LCd、960 μmol/LMo+5 μmol/LCd)on the duck proximal tubular cells were investigated in the following assays.Effects of different doses of molybdenum and/or cadmium on the survival rates in duck proximal tubular cells for a time range of 3,6,12 and 24 h were detected;Effects of molybdenum and/or cadmium on the LDH release activities of SOD,T-AOC and contents of GSH,MDA in duck proximal tubular cells were measured when exposed to molybdenum and/or cadmium over a 12 h period.LDH release and the protective effect of N-acetyl-L-cysteine(NAC)against molybdenum and/or cadmium induced cellular damage was investigated.The results show that(1)alkaline phosphatase staining showed that tubular epithelial cells were dyed black and control cells were not stained,the study show that duck tubular epithelial cells was more than 95%.(2)The primary cell growth curve: the growth stage in 24 h,logarithmic phase in24h~88h and cell activity is the strongest in 78 h,enters the stationary phase in 90 h.the duck proximal tubular cells were investigated in the following assays: the growth stage in12 h,logarithmic phase in12 h~70 h and cell activity is strongest in56 h,enters the stationary phase in70 h.(3)(NH4)6Mo7O24·4H2O and 3CdSO4·8H2O exposure of IC50 is 1773.64 μmol/LMo、24.17μmol/L Cd at 12 h.(4)the cell survival rates: the single high-dose molybdenum groups and cadmium groups were significantly lower than those of control groups since these cells were for three hours,respectively(P<0.01).The single low-dose molybdenum groups were significantly lower than those of control groups since these cells were for 6 h,respectively(P<0.05).The cell survival rates in the combined groups were significantly lower than those of control groups after a 3 h exposure(P<0.01).Furthermore,the degree of decrease in the cell survival rate was positively correlated with the dose and the exposure time.Factorial analysis showed that from the beginning of exposure 12 h interaction between cadmium and molybdenum(P<0.05).NAC can improve the survival rate of the exposed group(P<0.01).(5)After exposure to molybdenum and/or cadmium for 12 h,LDH release in these exposed groups were significantly higher than those in the control group(P<0.01).Apoptosis induced by molybdenum and/or cadmium can be efficiently prevented by NAC,but the necrotic rates and LDH release were not affected by NAC.(6)Compared with the control group,activities of SOD,T-AOC and the GSH level in the exposed groups decreased significantly(P<0.05 or P<0.01);But the content of MDA increased significantly(P<0.01).Based on these results,the conclusions are as follows: Molybdenum and/or cadmium exposure induced cellular death in duck proximal tubular cells,depending on both the concentration and the exposure time.Synergistic effect lies in the administration of lead combined with cadmium.Decreased activities of anti-oxidative enzymes further enhanced oxidative damage in duck proximal tubular cells caused by molybdenum and/or cadmium.In addition,the cellular damage induced by molybdenum and/or cadmium can be significantly prevented by NAC.