학술논문
Differences in the efficiency of 3-deazathiamine and oxythiamine pyrophosphates as inhibitors of pyruvate dehydrogenase complex and growth of HeLa cells in vitro.
Document Type
Article
Author
Source
Subject
*PYRUVATE dehydrogenase complex
*HELA cells
*VITAMIN B1
*THIAMIN pyrophosphate
*PYROPHOSPHATES
*CELL growth
*CELL culture
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Language
ISSN
1475-6366
Abstract
Oxythiamine (OT) and 3-deazathiamine (DAT) are the antimetabolites of thiamine. The aim of study was to compare the effects of OT and DAT pyrophosphates (-PP) on the kinetics of mammalian pyruvate dehydrogenase complex (PDHC) and the in vitro culture of HeLa cells. The kinetic study showed that 3-deazathiamine pyrophosphate (DATPP) was a much stronger competitive inhibitor (Ki = 0.0026 μM) of PDHC than OTPP (Ki = 0.025 μM). Both Ki values were much lower versus Km for thiamine pyrophosphate (0.06 μM). However, DATPP added to the culture medium for the HeLa cells culture did not hamper the rate of cell growth and showed not significant impact on the viability of the cells, whereas OTPP and OT showed a significant cytostatic effect. The differences between the thiamine antivitamins in their effect on cell growth in vitro may be due to differences in physicochemical properties and difficulty in DAT transport across the cell membrane. [ABSTRACT FROM AUTHOR]