The effect of melittin on proliferation and death of thymocytes

FEBS Letters

Korystov, Yu.N¹  Kudryavtsev, A.A¹  Shaposhnikova, V.V¹  Egorova, M.V¹  Levitman, M.Kh¹ 

[1] Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Moscow Region, Pushchino 142292, Russia

关键词: Apoptosis;    Melittin;    Necrosis;    Phospholipase A2;    Proliferation;    Thymocyte;    PLA2;    phospholipase A2;    EDTA;    ethylene diamine tetraacetic acid;    HEPES;    4-(2-hydroxyethyl)-1-piperazineethane-sulfonic acid;   

DOI  :  10.1016/S0014-5793(97)00578-4

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The effect of melittin, an activator of phospholipase A₂, on proliferation and death of rat thymocytes in a broad concentration range was studied. Cell proliferation was estimated by the accumulation of colchicin metaphases, necrotic death was determined from lysis and staining of cells with trypan blue, and apoptosis was assessed from the type of DNA fragmentation, the amount of fragmented DNA, and the percentage of cells with subdiploid DNA. It was shown that low melittin concentrations (below 5 μg/ml) stimulate thymocyte proliferation. At high melittin concentrations, thymocytes die by the primary necrosis type. Throughout the concentration range studied, melittin does not produce apoptosis in thymocytes. Conversely, high melittin concentrations even inhibit thymocyte apoptosis in the control and after irradiation. An inhibitor of RNA synthesis actinomycin D does not affect thymocyte death in the presence of melittin. It is concluded that the activation of phospholipase A₂ can induce necrosis but not apoptosis and thus is not a necessary step in the signaling cascade that initiates apoptosis in thymocytes.

【 授权许可】

Unknown