Experimental Study On The Antagonism Of Mineral Elements On Toxicity Of Silicon Dioxide

Silicon dioxide is the primary factor of pneumoconious. A lot of evidences suggested that it has cellular toxicity and hereditary toxicity.Mineral element especially trace elements are ingredients of vitamine, enzyme, protein, trypsin and nucleic acid, which play important roles in many chemical reactions in human body, act as special activation center in enzyme system. Mineral elements—magnesium, manganese, selenium, and zinc—act as cofactors of antioxidant enzymes to protect the body from free radicals that are produced during ROS and RNS. It is necessary to maintain a balance between the harmful pro-oxidant components produced and the antioxidant compounds that counter these effects.To study the single effects of magnesium and combined antagonistic action of zinc, selenium, magnesium and manganese on the toxicity of SiO2, a series of assays had been conducted, including cytotoxicity assays, genotoxicity assays.The results were as follows.Technique of obtaining and purifying alveolar macrophages (AM) was feasible in this experiment system. In order to investigate the effects of magnesium sulfate which was used singly and zinc gluconate, sodium selenite, manganous chloride which were used together with magnesium sulfate respectively and the four elements were used all together on the cytotoxicity in AM exposed to SiO2, Some biochemical characterizations were measued. The results showed magnesium sulfate singly and zinc gluconate , sodium selenite, manganous chloride coupled with magnesium sulfate respectively and the four elements all together can decrease the levels of nitric oxide (NO), nitric oxide synthesize enzyme (NOS), lactic dehydrogenase (LDH), malondialdehyde (MDA) and H₂O₂, and increase the activities of antioxidant enzyme such as glutathione (GSH-Px), superoxide dismutase(SOD) and catalase (CAT).The most suitable combinations of twosome were 1.5mg/L of zinc gluconate with 2.0μmol/L of magnesium sulfate , 1.0μmol/L of sodium selenite with 1.0μmol/L of magnesium sulfate, 0.5mg/L of manganous chloride with 2.0μmol/L of magnesium sulfate, 1.0 mg/L of manganous chloride with 1.0μmol/L of sodium selenite. The most suitable combination of quaternion was 1.5 mg/L of zinc gluconate, 1.0μmol/L sodium selenite, 1.0mg/L manganous chloride with 0.5μmol/L of magnesium sulfate.Single cell gel electrophoresis (SCGE) assay was used to study the effects of magnesium sulfate which was used solely and zinc gluconate , sodium selenite, manganous chloride and magnesium sulfate which were used by twos or quaternity antagonize DNA strand break of HFL induced by silicon dioxide. DNA damage of HFL exposed by silica could be observed through SCGE assay ,magnesium sulfate which was used singly and zinc gluconate , sodium selenite, manganous chloride which were used together with magnesium sulfate respectively and the four elements were used all together could lighten DNA damage induced by silica, and the most suitable combinations by twos were 1.5mg/L of zinc gluconate with 2.0μmol/L of magnesium sulfate, 1.0μmol/L of sodium selenite with 2.0μmol/L of magnesium sulfate, 1.0mg/L of manganous chloride with 1.0μmol/L of sodium selenite. There is a particular case, when manganous chloride was used with magnesium sulfate, their effets was difference on the comet percent and the comet tail length.On the comet percent the optimal combination was 0.5mg/L of manganous chloride with 2.0μmol/L of magnesium sulfate; but when the comet tail length was observed the best combination was 1.0mg/L of manganous chloride with 1.0μmol/L of magnesium sulfate. The...