Tag Archives: retinoids
Hepatotoxicity of bisphenol A under conditions of differential supplementation with retinoids
I. O. Shmarakov, V. L. Borschovetska, L. P. Ivanishchuk, M. M. Marchenko
Yuriy Fed’kovych Chernivtsi National University, Ukraine;
e-mail: igor.shmarakov@gmail.com
Classical xenoestrogenic in vivo effects of bisphenol A (2,2-bis(4-hydroxyphenyl)propane, BPA) are well-described in the literature, however the molecular mechanisms of BPA-induced hepatotoxicity are not fully characterized. The work is aimed to assess biochemical markers of BPA induced hepatotoxicity under conditions of differential supplementation with retinoids. We demonstrate that the absence of hepatic retinyl esters as the main form of vitamin A storage provides for a resistance to BPA induced liver damage. Retinoid supplementation increases the hepatotoxic effects of bisphenol A, evidenced in higher indexes of oxidative damage of lipids, proteins and non-protein thiol groups as well as increase of serum alanine aminotransferase activity and myeloperoxidase activity in liver parenchyma. The absence of hepatotoxicity signs when hepatic retinoid stores are depleted and their presence during normal or excessive retinoid supplementation suggest that hepatic retinoid availability is one of the factors determining the hepatotoxicity of bisphenol A.
Activity of enzymatic detoxification systems in the mice liver under conditions of different retinoid provision
М. M. Marchenko, G. P. Kopylchuk, I. O. Shmarakov, I. M. Buchkovska
Yuriy Fedkovych Chernivtsi National University, Ukraine;
e-mail: ivannabuchkovska@mail.ru
The activity of cellular components of liver detoxification system was studied under the conditions of the absence of vitamin A stores. It is shown that a decrease of p-hydroxylase and N-demethylase activity of cytochrome P-450 simultaneously with a decrease of glutathione-S-transferase activity takes place in the liver microsomal fraction of vitamin A-deficient animals. At the same time the absence of retinoid stores in knock-out animals influences the decrease of only p-hydroxylase activity of cytochrome P-450 system. The increase in glutathione-S-transferase activity is observed in the liver postmicrosomal fraction in mice, kept on vitamin A-deficient diet, while its parametres in knock-out group animals were not statistically different compared to the control.