Tag Archives: pyridoxine

Effects of L-glutamic acid and pyridoxine on glutathione depletion and lipid peroxidation generated by epinephrine-induced stress in rats

N. O. Salyha

Institute of Animal Biology, NAAS of Ukraine, Lviv;
е-mail: ynosyt@yahoo.com

The main goal of this research was to investigate and compare the protective effects of L-glutamic acid (L-Glu) alone and combined with Pyridoxine (L-Glu+Pyridoxine) for the purpose of suppression and mitigation of epinephrine-induced stress in rats. This study outlines possible links between changes of reduced glutathione (GSH) level, antioxidant enzymes activity and content of the lipid peroxidation products after administration of the above-mentioned substances and under the action of stress in various tissues of rats. The obtained results suggest that the GSH level was significantly inhibited by stress in all investigated tissues (except kidneys). We have shown that under the stress, activities of glutathione-associated enzymes were changed (mainly decreased) in all investigated tissues. In rats, additionally received L-Glu and L-Glu+Pyridoxine, much less changes or lack of changes in studied parameters were observed. The content of lipid peroxidation products (lipid peroxides (LOOH) and thiobarbituric acid reactive substances (TBARS)) in myocardium, liver and kidney tissues of experimental groups under the stress conditions were significantly higher compared to the control. While in experimental groups that received L-Glu and L-Glu+Pyridoxine LOOH content in kidney, spleen and liver and TBARS content in spleen, liver and myocardium were almost at the level of control values. These results indicate that L-Glu and L-Glu+Pyridoxine can mitigate and suppress epinephrine-induced stress in rats.

Physical-chemical properties and the reactivity of pyridoxine and pyrrolidone carboxylate and their protolytic forms

N. Ya. Golovenko, V. B. Larionov, O. V. Karpova

A. V. Bogatsky Physical-Chemical Institute, National Academy
of Sciences of Ukraine, Odessa;
e-mail: lvb_78@ukr.net

Preparation Methadoxine is equimolar salt, which cationic component (pyridoxine) is 3-oxypyridine derivative, possessing B6-vitamine like activity, while anionic component is the cyclic lactame of glutamic acid. Since biopharmaceutical and pharmacological properties of this drug depend on biochemical transformation its components, of the aim of this work was to determine the structure of possible ionized pyridoxine and pyrrolidone carboxylate forms and their reaction ability in biochemical processes. Physical-chemical properties of compounds (pKa, logP, logD, proton donor/acceptor quantity, solubility (g/l)) were calculated with ACD/pKaDB program or obtained from Pub-Med physical/chemical properties database. UV spectra of compounds were obtained after dissolution in different pH solutions (1.0, 4.5 and 6.8). It was found that at different pH values one can observe changes of the absorption spectra due to the presence of prevailing amount of the protonated form.  An analysis of both pKa, logP and logD indicators and reactive functional groups of Methadoxine components has revealed that they can be protonated in different regions of gastro-intestinal tract, that influences their solubility in hydrophilic and lypophilic media. Pharmacological properties of pyridoxine and pyrrolidone carboxylate themselves are performed after their preliminary biotransformation to active metabolites. Only ionic interaction between Methadoxine components in the substance composition can appear, that provides its pharmaceutical stability and ensures its activity only in the orga­nism conditions.