Tag Archives: dimedone

Method for endogenous formaldehyde evaluation in animal organism

S. G. Shandrenko, M. M. Savchyk, M. P. Dmytrenko

Palladin Institute of Biochemistry, National Academy of Sciences of Ukraine, Kyiv;
e-mail: shandrenko@biochem.kiev.ua

A method for endogenous formaldehyde (FA) level evaluation has been worked out. The method involves the administration of dimedone, which forms the stable complex with FA, and the determination of formaldimedone concentration in biological samples by the fluorescence approach. The method was tested on rat’s models of FA metabolism modulation. Animals received FA (10 mg/kg); or methylamine – substrate of FA-generating enzyme SSAO, (250 mg/kg); or semicarbazide – SSAO inhibitor, (200mg/kg). Concentration of FA bound with dimedone in the liver tissue were, correspondingly: 7.5 ± 1.5 mkg/kg; 5.4 ± 0.9 mkg/kg; 2.4 ± 0.7 mkg/kg; control – 4.2 ± 1.4 mkg/kg. Obtained data indicate, that the elaborated method gives reliable information about FA level.

Aldehydes participation in oxidative stress in rat thymocytes in vitro

K. О. Tokarchuk, О. V. Zaitseva

Palladin Institute of Biochemistry, National Academy of Sciences of Ukraine, Kyiv;
e-mail: kate_tokarchuk@ukr.net

A variety of lipid radicals are formed under oxidative stress development. The further oxidation of these radicals leads to formation of numerous aldehydes. They can form postsynthetic modifications in proteins and nucleic acids that disrupt their functions. In the present study aldehydes role in the formation of oxidative stress parameters in rat thymocytes was investigated. Two models were used: iron-stimulated oxidative stress and exogenous aldehydes exposure to thymocytes.
For oxidative stress induction, thymocytes (2×106 cells/ml HBSS, рН 7.2) were exposed to different concentrations of FeSO4 (20, 30, 40 μМ) and ascorbic acid (100 μМ) for 6 h. It resulted in increase of levels of aldehydes 29 times (90 ± 6 nmol/107 cells), these changes led to increase of TBARS levels 4.4 times; the levels of protein CO groups 10 times, cell mitochondrial activity and low-molecular weight SH groups were decreased 1.5 and 2.3 times, respectively. Treatment with aldehydes acceptor dimedone (200 μМ) significantly decreased the levels of aldehydes 3.7 times, TBARS 1.6 times and protein CO groups 5 times. It was shown that the levels of cell mitochondrial activity increase 1.4 times and the levels of SH groups 1.8 times.
To compare the effects of aldehydes in induction of oxidative stress, thymocytes (2×106 cells/ml HBSS, рН 7.2) were exposed to 50-600 μМ formaldehyde (FA), 50-600 μМ glyoxal (GL), 50-600 μМ methylglyoxal (MGL), 1-15 μМ acrolein (АCR) for 6 h. TBARS levels were increased for FA 1.3 times and for other aldehydes  about 5-7 times. The levels of protein CO groups were increase for FA 3.7 times, for MGL 7 times, for GL 13 times, for ACR 22 times. Levels of SH groups were decreased for FA 1.5 times, for MGL 2.6 times, for GL 3 times, for ACR 9 times. A decrease of cell mitochondrial activity 1.5 times observe for all aldehydes. Obtained results prove the aldehydes participation in the formation of oxidative stress parameters and their capability to oxidative stress induction in the rat thymocytes.