XXII. BIOCHEMICKÝ ZJAZD - Jesseniova lekárska fakulta

Lectures
Apoptosis – DOUBLE EDGED SWORD
Peter Račay 1 , Jozef Hatok 1 , Mária Chomová 1 , Jana Jurečeková 1 , Peter Chudý 2 ,
Juraj Chudej 2 , Andrea Štefániková 1 and Dušan Dobrota 1
1
Department of Medical Biochemistry,
2
Clinic of Haematology and Transfusiology, JLF UK Martin
Apoptosis is an evolutionarily conserved process that is crucial for development and homeostasis
of tissues of multicellular organisms. Its deregulation can elicit inappropriate
cell death associated with different diseases (e. g. neurodegenerative diseases, diabetes,
etc.) or is associated with survival of undifferentiated or transformed cells and can lead
to development of cancer.
Here we present results documenting initiation of apoptosis after global brain ischemia as
well as dysfunction of apoptosis execution associated with acute myeloblastic leukaemia.
We have documented that global brain ischemia induces transcription independent p53-
mediated mitochondrial apoptosis. Execution of apoptosis was associated with genomic
DNA fragmentation and death of pyramidal neurones in CA1 layer of rat hippocampus.
On the other hand, RT-PCR analysis documented significant increase of mRNA level of
apoptotic protein Bax in leukaemic cells in comparison to normal leukocytes, indicating
transcription dependent initiation of p53-mediated apoptosis. Despite apoptosis initiation,
survival of leukaemic cells is probably associated with inhibition of apoptosis execution
mediated by increased transcription of both bcl-X and bcl-2 genes.
Our results showed that detailed study of mechanism of apoptosis might by useful in
search for new effective treatment of diseases associated with either cell death or cell
survival due to deregulation of apoptosis.
Acknowledgement: This work was supported by grant VVCE 0064-07
XXII. Biochemistry Congress, Martin
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