Tellurium tetrachloride and diphenyl ditelluride cause cytotoxicity in rat hippocampal astrocytes

详细信息    查看全文

• 作者：Shalini Roy ; Diane Hardej  ; ;   ; ^{hardejd@stjohns.edu}
• 关键词：Tellurium tetrachloride ; Diphenyl ditelluride ; Rat hippocampal astrocytes ; Cytotoxicity ; Tellurium
• 刊名：Food and Chemical Toxicology
• 出版年：2011
• 出版时间：October 2011
• 年：2011
• 卷：49
• 期：10
• 页码：2564-2574
• 全文大小：1921 K

文摘

Tellurium tetrachloride (TeCl₄) and diphenyl ditelluride (DPDT) cytotoxicity, was investigated in rat astrocytes. Concentrations of 0.24?50 ¦ÌM (24 h) were tested for viability using MTT(3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide) and trypan blue exclusion. MTT showed significant decreases at all concentrations tested for both compounds. Significant decreases in viability were seen in 1.95?50 ¦ÌM of DPDT and 0.97?50 ¦ÌM of TeCl₄ with trypan blue exclusion. The LC₅₀ for both compounds was 62.5 ¦ÌM. Light and scanning microscopy confirm toxicity observed at higher concentrations. Thiobarbituric acid reactive substances (TBARs) assay, TUNEL, cytochrome c and caspase release were carried out. No significant increase in TBARS with either agent was observed (15.625?2.5 ¦ÌM). TUNEL and cytochrome c assays demonstrated apoptosis in TeCl₄ treated cells (31.25?25 ¦ÌM). Non-apoptotic cells were observed in DPDT treated cells. Studies of caspase 3/7 and caspase 9 indicated increased activity in TeCl₄ but not in DPDT treated cells. Optical Emission Spectroscopy of DPDT and TeCl₄ treated cells demonstrated significant accumulation of elemental tellurium in all treatment groups (31.25?25 ¦ÌM). We conclude that DPDT and TeCl₄ are cytotoxic to astrocytes. TeCl₄ treated cells die via the intrinsic apoptotic pathway. Accumulation of tellurium occurs with both compounds, but results in different mechanisms of cell death.